A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting the URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting a URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured File Policy for HTTP. The vulnerability is due to incorrect detection of modified HTTP packets used in chunked responses. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass a configured File Policy for HTTP packets and deliver a malicious payload.

Cisco IP Communicator 8.6 allows man-in-the-middle attackers to modify the Certificate Trust List via unspecified vectors, aka Bug ID CSCtz01471.

Cisco Cache Engine allows an attacker to replace content in the cache.

OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). The AES GCM decryption routine incorrectly uses the Tag length from the actual Authentication Tag provided in the JWE. The spec says that a fixed length of 16 octets must be applied. Therefore this bug allows an attacker to provide a truncated Authentication Tag and to modify the JWE accordingly. Users should upgrade to a version >= 0.6.2.2. Users unable to upgrade should avoid using AES GCM encryption and replace it with another encryption algorithm (e.g. AES CBC).

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) protocol inspection engine of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the configured file policies on an affected system. The vulnerability is due to errors when handling specific SSL/TLS messages. An attacker could exploit this vulnerability by sending crafted HTTP packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured file policies and deliver a malicious payload to the protected network.

A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured filters on the device. The vulnerability is due to improper input validation of certain email fields. An attacker could exploit this vulnerability by sending a crafted email message to a recipient protected by the ESA. A successful exploit could allow the attacker to bypass configured message filters and inject arbitrary scripting code inside the email body. The malicious code is not executed by default unless the recipient's email client is configured to execute scripts contained in emails.

A vulnerability in the GZIP decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper validation of GZIP-formatted files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted GZIP-compressed file. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.

A vulnerability in Cisco TelePresence Video Communication Server (VCS) and Cisco Expressway Series software could allow an unauthenticated, remote attacker to cause an affected system to send arbitrary network requests. The vulnerability is due to improper restrictions on network services in the affected software. An attacker could exploit this vulnerability by sending malicious requests to the affected system. A successful exploit could allow the attacker to send arbitrary network requests sourced from the affected system.

A vulnerability in the attachment scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper input validation of the email body. An attacker could exploit this vulnerability by naming a malicious attachment with a specific pattern. A successful exploit could allow the attacker to bypass configured content filters that would normally block the attachment.

A vulnerability in the normalization functionality of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to insufficient normalization of a text-based payload. An attacker could exploit this vulnerability by sending traffic that contains specifically obfuscated payloads through an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious payloads to protected systems that would otherwise be blocked.

A vulnerability in the Sender Policy Framework (SPF) functionality of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) could allow an unauthenticated, remote attacker to bypass configured user filters on the device. The vulnerability is due to incomplete input and validation checking mechanisms for certain SPF messages that are sent to an affected device. An attacker could exploit this vulnerability by sending a customized SPF packet to an affected device. A successful exploit could allow the attacker to bypass the header filters that are configured for the affected device, which could allow malicious content to pass through the device.

A vulnerability in the HTTP traffic filtering component of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to improper handling of HTTP requests, including those communicated over a secure HTTPS connection, that contain maliciously crafted headers. An attacker could exploit this vulnerability by sending malicious requests to an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious requests to protected systems, allowing attackers to deliver malicious content that would otherwise be blocked.

A vulnerability in the packet filtering features of Cisco SD-WAN Solution could allow an unauthenticated, remote attacker to bypass L3 and L4 traffic filters. The vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by crafting a malicious TCP packet with specific characteristics and sending it to a target device. A successful exploit could allow the attacker to bypass the L3 and L4 traffic filters and inject an arbitrary packet in the network.

A vulnerability in the implementation of the Simple Network Management Protocol (SNMP) Access Control List (ACL) feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to perform SNMP polling of an affected device, even if it is configured to deny SNMP traffic. The vulnerability is due to an incorrect length check when the configured ACL name is the maximum length, which is 32 ASCII characters. An attacker could exploit this vulnerability by performing SNMP polling of an affected device. A successful exploit could allow the attacker to perform SNMP polling that should have been denied. The attacker has no control of the configuration of the SNMP ACL name.

A vulnerability in the HTTPS proxy feature of Cisco Wide Area Application Services (WAAS) Software could allow an unauthenticated, remote attacker to use the Central Manager as an HTTPS proxy. The vulnerability is due to insufficient authentication of proxy connection requests. An attacker could exploit this vulnerability by sending a malicious HTTPS CONNECT message to the Central Manager. A successful exploit could allow the attacker to access public internet resources that would normally be blocked by corporate policies.

A vulnerability in the protocol detection component of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to improper detection of the initial use of a protocol on a nonstandard port. An attacker could exploit this vulnerability by sending traffic on a nonstandard port for the protocol in use through an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious requests to protected systems that would otherwise be blocked. Once the initial protocol flow on the nonstandard port is detected, future flows on the nonstandard port will be successfully detected and handled as configured by the applied policy.

A vulnerability in the stream reassembly component of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to improper reassembly of traffic streams. An attacker could exploit this vulnerability by sending crafted streams through an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious requests to protected systems that would otherwise be blocked.

Cisco Carrier Routing System (CRS) 3.9, 4.0, and 4.1 allows remote attackers to bypass ACL entries via fragmented packets, aka Bug ID CSCtj10975.

A vulnerability in the implementation of Security Assertion Markup Language (SAML) 2.0 Single Sign-On (SSO) for Clientless SSL VPN (WebVPN) and AnyConnect Remote Access VPN in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to successfully establish a VPN session to an affected device. The vulnerability is due to improper credential management when using NT LAN Manager (NTLM) or basic authentication. An attacker could exploit this vulnerability by opening a VPN session to an affected device after another VPN user has successfully authenticated to the affected device via SAML SSO. A successful exploit could allow the attacker to connect to secured networks behind the affected device.

A vulnerability in the detection engine of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured access control policies. The vulnerability is due to improper validation of ICMP packets. An attacker could exploit this vulnerability by sending crafted ICMP packets to the affected device. A successful exploit could allow the attacker to bypass configured access control policies.

A vulnerability in certain attachment detection mechanisms of the Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the filtering functionality of an affected device. The vulnerability is due to improper detection of certain content sent to an affected device. An attacker could exploit this vulnerability by sending certain file types without Content-Disposition information to an affected device. A successful exploit could allow an attacker to send messages that contain malicious content to users.

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) protocol parser of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured policies. The vulnerability is due to improper parsing of specific attributes in a TLS packet header. An attacker could exploit this vulnerability by sending malicious TLS messages to the affected system. A successful exploit could allow the attacker to bypass the configured policies for the system, which could allow traffic to flow through without being inspected.

A vulnerability in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper input validation of the email body. An attacker could exploit this vulnerability by inserting specific character strings in the message. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.

Cisco Small Business IP phones with SPA 500 series firmware 7.4.9 and earlier do not require authentication for Push XML requests, which allows remote attackers to make telephone calls via an XML document, aka Bug ID CSCts08768.

A vulnerability in the configuration import utility of Cisco Integrated Management Controller (IMC) could allow an unauthenticated, remote attacker to have write access and upload arbitrary data to the filesystem. The vulnerability is due to a failure to delete temporarily uploaded files. An attacker could exploit this vulnerability by crafting a malicious file and uploading it to the affected device. An exploit could allow the attacker to fill up the filesystem or upload malicious scripts.

Cisco IOS 12.2 through 12.4 and 15.0 does not recognize the vrf-also keyword during enforcement of access-class commands, which allows remote attackers to establish TELNET connections from arbitrary source IP addresses via a standard TELNET client, aka Bug ID CSCsi77774.

A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. The vulnerability is due to insufficient input validation of URLs. An attacker could exploit this vulnerability by crafting the URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

Cisco IOS 12.2 through 12.4 and 15.0 does not recognize the vrf-also keyword during enforcement of access-class commands, which allows remote attackers to establish SSH connections from arbitrary source IP addresses via a standard SSH client, aka Bug ID CSCsv86113.

A vulnerability in the Dialer interface feature for ISDN connections in Cisco IOS XE Software for Cisco 4000 Series Integrated Services Routers (ISRs) could allow an unauthenticated, adjacent attacker to pass IPv4 traffic through an ISDN channel prior to successful PPP authentication. The vulnerability is due to insufficient validation of the state of the PPP IP Control Protocol (IPCP). An attacker could exploit this vulnerability by making an ISDN call to an affected device and sending traffic through the ISDN channel prior to successful PPP authentication. Alternatively, an unauthenticated, remote attacker could exploit this vulnerability by sending traffic through an affected device that is configured to exit via an ISDN connection for which both the Dialer interface and the Basic Rate Interface (BRI) have been configured, but the Challenge Handshake Authentication Protocol (CHAP) password for PPP does not match the remote end. A successful exploit could allow the attacker to pass IPv4 traffic through an unauthenticated ISDN connection for a few seconds, from initial ISDN call setup until PPP authentication fails.

A vulnerability in the Sender Policy Framework (SPF) functionality of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the configured user filters on an affected device. The vulnerability exists because the affected software insufficiently validates certain incoming SPF messages. An attacker could exploit this vulnerability by sending a custom SPF packet to an affected device. A successful exploit could allow the attacker to bypass the configured header filters, which could allow malicious content to pass through the device.

A vulnerability in Cisco Finesse could allow an unauthenticated, remote attacker to bypass access controls and conduct a server-side request forgery (SSRF) attack on an affected system. The vulnerability exists because the affected system does not properly validate user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to a user of the web application. A successful exploit could allow the attacker to access the system and perform unauthorized actions.

Multiple vulnerabilities in the Cisco Firepower System Software Detection Engine could allow an unauthenticated, remote attacker to bypass configured Malware and File Policies for RTF and RAR file types. For more information about these vulnerabilities, see the Details section of this advisory.

CRLF injection vulnerability in /+CSCOE+/logon.html on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.0 through 8.4 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via unspecified vectors, aka Bug ID CSCth63101.

Duo Network Gateway 1.2.9 and earlier may incorrectly utilize the results of XML DOM traversal and canonicalization APIs in such a way that an attacker may be able to manipulate the SAML data without invalidating the cryptographic signature, allowing the attack to potentially bypass authentication to SAML service providers.

A vulnerability in the Security Intelligence feed feature of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass the Security Intelligence DNS feed. This vulnerability is due to incorrect feed update processing. An attacker could exploit this vulnerability by sending traffic through an affected device that should be blocked by the affected device. A successful exploit could allow the attacker to bypass device controls and successfully send traffic to devices that are expected to be protected by the affected device.

A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass a configured Intrusion Prevention System (IPS) rule that inspects certain types of TCP traffic. The vulnerability is due to incorrect TCP retransmission handling. An attacker could exploit this vulnerability by sending a crafted TCP connection request through an affected device. A successful exploit could allow the attacker to bypass configured IPS rules and allow uninspected traffic onto the network.

A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass a configured file action policy that is intended to drop the Server Message Block Version 2 (SMB2) and SMB Version 3 (SMB3) protocols if malware is detected. The vulnerability is due to incorrect detection of an SMB2 or SMB3 file based on the total file length. An attacker could exploit this vulnerability by sending a crafted SMB2 or SMB3 transfer request through the targeted device. An exploit could allow the attacker to pass SMB2 or SMB3 files that could be malware even though the device is configured to block them. This vulnerability does not exist for SMB Version 1 (SMB1) files. This vulnerability affects Cisco Firepower System Software when one or more file action policies are configured, on software releases prior to 6.2.3. Cisco Bug IDs: CSCvg68807.

A vulnerability in the Secure Sockets Layer (SSL) Virtual Private Network (VPN) Client Certificate Authentication feature for Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to establish an SSL VPN connection and bypass certain SSL certificate verification steps. The vulnerability is due to incorrect verification of the SSL Client Certificate. An attacker could exploit this vulnerability by connecting to the ASA VPN without a proper private key and certificate pair. A successful exploit could allow the attacker to establish an SSL VPN connection to the ASA when the connection should have been rejected. This vulnerability affects Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) Software that is running on the following Cisco products: 3000 Series Industrial Security Appliances (ISA), ASA 5500 Series Adaptive Security Appliances, ASA 5500-X Series Next-Generation Firewalls, ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Adaptive Security Virtual Appliances (ASAv), Firepower 4110 Security Appliances, Firepower 9300 ASA Security Modules. Cisco Bug IDs: CSCvg40155.

A vulnerability in the detection engine of Cisco FireSIGHT System Software could allow an unauthenticated, remote attacker to bypass a URL-based access control policy that is configured to block traffic for an affected system. The vulnerability exists because the affected software incorrectly handles TCP packets that are received out of order when a TCP SYN retransmission is issued. An attacker could exploit this vulnerability by sending a maliciously crafted connection through an affected device. A successful exploit could allow the attacker to bypass a URL-based access control policy that is configured to block traffic for the affected system. Cisco Bug IDs: CSCvh84511.

A vulnerability in the file type detection mechanism of the Cisco Advanced Malware Protection (AMP) for Endpoints macOS Connector could allow an unauthenticated, remote attacker to bypass malware detection. The vulnerability occurs because the software relies on only the file extension for detecting DMG files. An attacker could exploit this vulnerability by sending a DMG file with a nonstandard extension to a device that is running an affected AMP for Endpoints macOS Connector. An exploit could allow the attacker to bypass configured malware detection. Cisco Bug IDs: CSCve34034.

A vulnerability in the detection engine of Cisco Firepower Threat Defense software could allow an unauthenticated, remote attacker to bypass a configured Secure Sockets Layer (SSL) Access Control (AC) policy to block SSL traffic. The vulnerability is due to the incorrect handling of TCP SSL packets received out of order. An attacker could exploit this vulnerability by sending a crafted SSL connection through the affected device. A successful exploit could allow the attacker to bypass a configured SSL AC policy to block SSL traffic. Cisco Bug IDs: CSCvg09316.

A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass configured file action policies if an Intelligent Application Bypass (IAB) with a drop percentage threshold is also configured. The vulnerability is due to incorrect counting of the percentage of dropped traffic. An attacker could exploit this vulnerability by sending network traffic to a targeted device. An exploit could allow the attacker to bypass configured file action policies, and traffic that should be dropped could be allowed into the network. Cisco Bug IDs: CSCvf86435.

A vulnerability in the session identification management functionality of the web-based interface of Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to hijack a valid user session on an affected system. The vulnerability exists because the affected software does not properly clear previously assigned session identifiers for a user session when a user authenticates to the web-based interface. An attacker could exploit this vulnerability by using an existing session identifier to connect to the software through the web-based interface. Successful exploitation could allow the attacker to hijack an authenticated user's browser session on the system. Versions 8.1 and 8.5 are affected.

A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass a configured file action policy to drop the Server Message Block (SMB) protocol if a malware file is detected. The vulnerability is due to how the SMB protocol handles a case in which a large file transfer fails. This case occurs when some pieces of the file are successfully transferred to the remote endpoint, but ultimately the file transfer fails and is reset. An attacker could exploit this vulnerability by sending a crafted SMB file transfer request through the targeted device. An exploit could allow the attacker to pass an SMB file that contains malware, which the device is configured to block. This vulnerability affects Cisco Firepower System Software when one or more file action policies are configured, on software releases prior to 6.2.3. Cisco Bug IDs: CSCvc20141.

A vulnerability in the detection engine of Cisco FireSIGHT System Software could allow an unauthenticated, remote attacker to bypass a file policy that is configured to block the transfer of files to an affected system via FTP. The vulnerability exists because the affected software incorrectly handles FTP control connections. An attacker could exploit this vulnerability by sending a maliciously crafted FTP connection to transfer a file to an affected device. A successful exploit could allow the attacker to bypass a file policy that is configured to apply the Block upload with reset action to FTP traffic. Cisco Bug IDs: CSCvh70130.

A vulnerability in the Cisco node-jose open source library before 0.11.0 could allow an unauthenticated, remote attacker to re-sign tokens using a key that is embedded within the token. The vulnerability is due to node-jose following the JSON Web Signature (JWS) standard for JSON Web Tokens (JWTs). This standard specifies that a JSON Web Key (JWK) representing a public key can be embedded within the header of a JWS. This public key is then trusted for verification. An attacker could exploit this by forging valid JWS objects by removing the original signature, adding a new public key to the header, and then signing the object using the (attacker-owned) private key associated with the public key embedded in that JWS header.

The Comcast firmware on Cisco DPC3939 (firmware version dpc3939-P20-18-v303r20421746-170221a-CMCST) devices allows remote attackers to write arbitrary data to a known /var/tmp/sess_* pathname by leveraging the device's operation in UI dev mode.