The Authentication Proxy feature in Cisco IOS does not properly handle invalid AAA return codes from RADIUS and TACACS+ servers, which allows remote attackers to bypass authentication in opportunistic circumstances via a connection attempt that triggers an invalid code, as demonstrated by a connection attempt with a blank password, aka Bug IDs CSCuo09400 and CSCun16016.

The management interface in Cisco TelePresence Video Communication Server (VCS) and Cisco Expressway before X7.2.4, X8 before X8.1.2, and X8.2 before X8.2.2 and Cisco TelePresence Conductor before X2.3.1 and XC2.4 before XC2.4.1 allows remote attackers to bypass authentication via crafted login parameters, aka Bug IDs CSCur02680 and CSCur05556.

Unspecified vulnerability in Cisco Adaptive Security Appliances (ASA) 5500 Series and PIX Security Appliances 7.0 before 7.0(8)3, 7.1 before 7.1(2)78, 7.2 before 7.2(4)16, 8.0 before 8.0(4)6, and 8.1 before 8.1(1)13, when configured as a VPN using Microsoft Windows NT Domain authentication, allows remote attackers to bypass VPN authentication via unknown vectors.

Unspecified vulnerability in Cisco Unity 4.x before 4.2(1)ES161, 5.x before 5.0(1)ES53, and 7.x before 7.0(2)ES8, when using anonymous authentication (aka native Unity authentication), allows remote attackers to bypass authentication and read or modify system configuration parameters by going to a specific link more than once.

The default configuration of Cisco Small Business IP phones SPA 300 7.5.5 and SPA 500 7.5.5 does not properly support authentication, which allows remote attackers to read audio-stream data or originate telephone calls via a crafted XML request, aka Bug ID CSCuo52482.

HTTP server for Cisco IOS 11.3 to 12.2 allows attackers to bypass authentication and execute arbitrary commands, when local authorization is being used, by specifying a high access level in the URL.

A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Supervisor, Cisco UCS Director, and Cisco UCS Director Express for Big Data could allow an unauthenticated, remote attacker to acquire a valid session token with administrator privileges, bypassing user authentication. The vulnerability is due to insufficient request header validation during the authentication process. An attacker could exploit this vulnerability by sending a series of malicious requests to an affected device. An exploit could allow the attacker to use the acquired session token to gain full administrator access to the affected device.

A vulnerability in the web-based management interface of Cisco Enterprise NFV Infrastructure Software (NFVIS) could allow an unauthenticated, remote attacker to bypass authentication and get limited access to the web-based management interface. The vulnerability is due to an incorrect implementation of authentication in the web-based management interface. An attacker could exploit this vulnerability by sending a crafted authentication request to the web-based management interface on an affected system. A successful exploit could allow the attacker to view limited configuration details and potentially upload a virtual machine image.

A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Supervisor, Cisco UCS Director, and Cisco UCS Director Express for Big Data could allow an unauthenticated, remote attacker to bypass user authentication and gain access as an administrative user. The vulnerability is due to insufficient request header validation during the authentication process. An attacker could exploit this vulnerability by sending a series of malicious requests to an affected device. An exploit could allow the attacker to gain full administrative access to the affected device.

A vulnerability in the web-based management interface of Cisco UCS Director and Cisco UCS Director Express for Big Data could allow an unauthenticated, remote attacker to bypass authentication and execute arbitrary actions with administrator privileges on an affected system. The vulnerability is due to improper authentication request handling. An attacker could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow an unprivileged attacker to access and execute arbitrary actions through certain APIs.

The play/modules component in Cisco WebEx Meetings Server allows remote attackers to obtain administrator access via crafted API requests, aka Bug ID CSCuj40421.

A vulnerability in access control list (ACL) functionality of the Gigabit Ethernet Management interface of Cisco IOS XE Software could allow an unauthenticated, remote attacker to reach the configured IP addresses on the Gigabit Ethernet Management interface. The vulnerability is due to a logic error that was introduced in the Cisco IOS XE Software 16.1.1 Release, which prevents the ACL from working when applied against the management interface. An attacker could exploit this issue by attempting to access the device via the management interface.

The Disaster Recovery (DRA) feature on the Cisco ISB8320-E High-Definition IP-Only DVR allows remote attackers to bypass authentication by establishing a TELNET session during a recovery boot, aka Bug ID CSCup85422.

A vulnerability in the session management functionality of the web-based interface for Cisco Small Business RV320 and RV325 Dual Gigabit WAN VPN Routers could allow an unauthenticated, remote attacker to hijack a valid user session on an affected system. An attacker could use this impersonated session to create a new user account or otherwise control the device with the privileges of the hijacked session. The vulnerability is due to a lack of proper session management controls. An attacker could exploit this vulnerability by sending a crafted HTTP request to a targeted device. A successful exploit could allow the attacker to take control of an existing user session on the device. Exploitation of the vulnerability requires that an authorized user session is active and that the attacker can craft an HTTP request to impersonate that session.

A vulnerability in the Graphite service of Cisco HyperFlex software could allow an unauthenticated, remote attacker to retrieve data from the Graphite service. The vulnerability is due to insufficient authentication controls. An attacker could exploit this vulnerability by sending crafted requests to the Graphite service. A successful exploit could allow the attacker to retrieve any statistics from the Graphite service. Versions prior to 3.5(2a) are affected.

A vulnerability in the hxterm service of Cisco HyperFlex Software could allow an unauthenticated, local attacker to gain root access to all nodes in the cluster. The vulnerability is due to insufficient authentication controls. An attacker could exploit this vulnerability by connecting to the hxterm service as a non-privileged, local user. A successful exploit could allow the attacker to gain root access to all member nodes of the HyperFlex cluster. This vulnerability affects Cisco HyperFlex Software Releases prior to 3.5(2a).

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.

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 upgrade mechanism of Cisco collaboration products based on the Cisco Voice Operating System software platform could allow an unauthenticated, remote attacker to gain unauthorized, elevated access to an affected device. The vulnerability occurs when a refresh upgrade (RU) or Prime Collaboration Deployment (PCD) migration is performed on an affected device. When a refresh upgrade or PCD migration is completed successfully, an engineering flag remains enabled and could allow root access to the device with a known password. If the vulnerable device is subsequently upgraded using the standard upgrade method to an Engineering Special Release, service update, or a new major release of the affected product, this vulnerability is remediated by that action. Note: Engineering Special Releases that are installed as COP files, as opposed to the standard upgrade method, do not remediate this vulnerability. An attacker who can access an affected device over SFTP while it is in a vulnerable state could gain root access to the device. This access could allow the attacker to compromise the affected system completely. Cisco Bug IDs: CSCvg22923, CSCvg55112, CSCvg55128, CSCvg55145, CSCvg58619, CSCvg64453, CSCvg64456, CSCvg64464, CSCvg64475, CSCvg68797.

A vulnerability in the smart card login authentication of Cisco Duo for macOS could allow an unauthenticated attacker with physical access to bypass authentication. This vulnerability exists because the assigned user of a smart card is not properly matched with the authenticating user. An attacker could exploit this vulnerability by configuring a smart card login to bypass Duo authentication. A successful exploit could allow the attacker to use any personal identity verification (PIV) smart card for authentication, even if the smart card is not assigned to the authenticating user.

The Clientless SSL VPN portal customization framework in Cisco ASA Software 8.2 before 8.2(5.51), 8.3 before 8.3(2.42), 8.4 before 8.4(7.23), 8.6 before 8.6(1.14), 9.0 before 9.0(4.24), 9.1 before 9.1(5.12), and 9.2 before 9.2(2.4) does not properly implement authentication, which allows remote attackers to modify RAMFS customization objects via unspecified vectors, as demonstrated by inserting XSS sequences or capturing credentials, aka Bug ID CSCup36829.

A vulnerability in the IPSec VPN Server authentication functionality of Cisco Small Business RV110W, RV130, RV130W, and RV215W Routers could allow an unauthenticated, remote attacker to bypass authentication controls and access the IPSec VPN network. This vulnerability is due to the improper implementation of the password validation algorithm. An attacker could exploit this vulnerability by logging in to the VPN from an affected device with crafted credentials. A successful exploit could allow the attacker to bypass authentication and access the IPSec VPN network. The attacker may obtain privileges that are the same level as an administrative user, depending on the crafted credentials that are used. Cisco has not released software updates that address this vulnerability.

The HSRP implementation in Cisco NX-OS 6.2(2a) and earlier allows remote attackers to bypass authentication and cause a denial of service (group-member state modification and traffic blackholing) via malformed HSRP packets, aka Bug ID CSCup11309.

A vulnerability in the login page of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to log in without credentials and access all roles without any restrictions. This vulnerability is due to exposed sensitive Security Assertion Markup Language (SAML) metadata. An attacker could exploit this vulnerability by using the exposed SAML metadata to bypass authentication to the user portal. A successful exploit could allow the attacker to access all roles without any restrictions.

The authentication-manager process in the web framework in Cisco Intrusion Prevention System (IPS) 7.0(8)E4 and earlier in Cisco Intrusion Detection System (IDS) does not properly manage user tokens, which allows remote attackers to cause a denial of service (temporary MainApp hang) via a crafted connection request to the management interface, aka Bug ID CSCuq39550.

The Administration GUI in the web framework in VOSS in Cisco Unified Communications Domain Manager (CDM) 9.0(.1) and earlier does not properly implement access control, which allows remote authenticated users to obtain sensitive user and group information by leveraging Location Administrator privileges and entering a crafted URL, aka Bug ID CSCum77005.

A vulnerability in the authentication functionality of Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to bypass authentication controls and log in to the device through the management interface This vulnerability is due to the improper implementation of the password validation algorithm. An attacker could exploit this vulnerability by logging in to an affected device with crafted credentials. A successful exploit could allow the attacker to bypass authentication and log in to the device as an administrator. The attacker could obtain privileges that are the same level as an administrative user but it depends on the crafted credentials. Note: This vulnerability exists because of a non-default device configuration that must be present for it to be exploitable. For details about the vulnerable configuration, see the Vulnerable Products section of this advisory.

The debug console interface on Cisco Small Business SPA300 and SPA500 phones does not properly perform authentication, which allows local users to execute arbitrary debug-shell commands, or read or modify data in memory or a filesystem, via direct access to this interface, aka Bug ID CSCun77435.

Cisco Adaptive Security Appliance (ASA) Software allows remote authenticated users to read files by sending a crafted URL to the HTTP server, as demonstrated by reading the running configuration, aka Bug ID CSCun78551.

The SSL VPN implementation in Cisco Adaptive Security Appliance (ASA) Software 8.2 before 8.2(5.47, 8.3 before 8.3(2.40), 8.4 before 8.4(7.3), 8.6 before 8.6(1.13), 9.0 before 9.0(3.8), and 9.1 before 9.1(3.2) allows remote attackers to bypass authentication via (1) a crafted cookie value within modified HTTP POST data or (2) a crafted URL, aka Bug ID CSCua85555.

The Disaster Recovery Framework (DRF) master server in Cisco Unified Communications products, including Unified Communications Manager (CUCM) 5.x and 6.x, Unified Presence 1.x and 6.x, Emergency Responder 2.x, and Mobility Manager 2.x, does not require authentication for requests received from the network, which allows remote attackers to execute arbitrary code via unspecified vectors.

The log4jinit web application in Cisco Unified Communications Manager (UCM) does not properly validate authentication, which allows remote attackers to cause a denial of service (performance degradation) via unspecified use of this application, aka Bug ID CSCum05347.

The Phone Proxy component in Cisco Adaptive Security Appliance (ASA) Software 9.1(.3) and earlier allows remote attackers to bypass authentication and change trust relationships by injecting a Certificate Trust List (CTL) file, aka Bug ID CSCuj66770.

The Enterprise License Manager (ELM) component in Cisco Unified Communications Manager (Unified CM) 10.0(1) and earlier does not properly enforce authentication requirements, which allows remote attackers to read ELM files via a direct request to a URL, aka Bug ID CSCum46494.

Race condition in the Phone Proxy component in Cisco Adaptive Security Appliance (ASA) Software 9.1(.3) and earlier allows remote attackers to bypass sec_db authentication and provide certain pass-through services to untrusted devices via a crafted configuration-file TFTP request, aka Bug ID CSCuj66766.

The Real Time Monitoring Tool (RTMT) web application in Cisco Unified Communications Manager (Unified CM) 10.0(1) and earlier does not properly enforce authentication requirements, which allows remote attackers to read application files via a direct request to a URL, aka Bug ID CSCum46495.

The Cisco Unified IP Phone 7960G 9.2(1) and earlier allows remote attackers to bypass authentication and change trust relationships by injecting a Certificate Trust List (CTL) file, aka Bug ID CSCuj66795.

Cisco Video Surveillance Operations Manager (VSOM) does not require authentication for MySQL database connections, which allows remote attackers to obtain sensitive information, modify data, or cause a denial of service by leveraging network connectivity from a client system with a crafted host name, aka Bug ID CSCud10992.

The Certificate Authority Proxy Function (CAPF) component in Cisco Unified Communications Manager (Unified CM) 10.0(1) and earlier allows remote attackers to bypass authentication and modify registered-device information via crafted data, aka Bug ID CSCum95468.

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.

Cisco Identity Services Engine (ISE) 1.x before 1.1.1 allows remote attackers to bypass authentication, and read support-bundle configuration and credentials data, via a crafted session on TCP port 443, aka Bug ID CSCty20405.

The remote-access VPN implementation in Cisco Adaptive Security Appliance (ASA) Software 7.x before 7.2(5.12), 8.x before 8.2(5.46), 8.3.x before 8.3(2.39), 8.4.x before 8.4(6), 8.6.x before 8.6(1.12), 9.0.x before 9.0(3.1), and 9.1.x before 9.1(2.5), when an override-account-disable option is enabled, does not properly parse AAA LDAP responses, which allows remote attackers to bypass authentication via a VPN connection attempt, aka Bug ID CSCug83401.

The Adaptive Security Device Management (ASDM) remote-management feature in Cisco Adaptive Security Appliance (ASA) Software 8.2.x before 8.2(5.46), 8.3.x before 8.3(2.39), 8.4.x before 8.4(6), 8.5.x before 8.5(1.18), 8.6.x before 8.6(1.12), 8.7.x before 8.7(1.7), 9.0.x before 9.0(3.1), and 9.1.x before 9.1(2.6) does not properly implement the authentication-certificate option, which allows remote attackers to bypass authentication via a TCP session to an ASDM interface, aka Bug ID CSCuh44815.

A vulnerability in the HTTP API of Cisco Enterprise Chat and Email could allow an unauthenticated, remote attacker to download files attached through chat sessions. The vulnerability is due to insufficient authentication mechanisms on the file download function of the API. An attacker could exploit this vulnerability by sending a crafted request to the API. A successful exploit could allow the attacker to download files that other users attach through the chat feature. This vulnerability affects versions prior to 12.0(1)ES1.

A vulnerability in the REST API of Cisco Elastic Services Controller (ESC) could allow an unauthenticated, remote attacker to bypass authentication on the REST API. The vulnerability is due to improper validation of API requests. An attacker could exploit this vulnerability by sending a crafted request to the REST API. A successful exploit could allow the attacker to execute arbitrary actions through the REST API with administrative privileges on an affected system.

A vulnerability in the Secure Shell (SSH) authentication function of Cisco IOS XR Software could allow an authenticated, remote attacker to successfully log in to an affected device using two distinct usernames. The vulnerability is due to a logic error that may occur when certain sequences of actions are processed during an SSH login event on the affected device. An attacker could exploit this vulnerability by initiating an SSH session to the device with a specific sequence that presents the two usernames. A successful exploit could result in logging data misrepresentation, user enumeration, or, in certain circumstances, a command authorization bypass. See the Details section for more information.

A vulnerability in the REST API interface of Cisco Vision Dynamic Signage Director could allow an unauthenticated, remote attacker to bypass authentication on an affected system. The vulnerability is due to insufficient validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected system. A successful exploit could allow the attacker to execute arbitrary actions through the REST API with administrative privileges on the affected system. The REST API is enabled by default and cannot be disabled.

Cisco Linksys Routers EA2700, EA3500, E4200, EA4500: A bug can cause an unsafe TCP port to open which leads to unauthenticated access

A vulnerability in 802.1x function of Cisco IOS Software on the Catalyst 6500 Series Switches could allow an unauthenticated, adjacent attacker to access the network prior to authentication. The vulnerability is due to how the 802.1x packets are handled in the process path. An attacker could exploit this vulnerability by attempting to connect to the network on an 802.1x configured port. A successful exploit could allow the attacker to intermittently obtain access to the network.

The administrative web interface in Cisco Video Surveillance Operations Manager does not properly perform authentication, which allows remote attackers to watch video feeds via a crafted URL, aka Bug ID CSCtg72262.