Cisco Secure Access Control Server (ACS) 3.2(3) and earlier spawns a separate unauthenticated TCP connection on a random port when a user authenticates to the ACS GUI, which allows remote attackers to bypass authentication by connecting to that port from the same IP address.

The Transaction Language 1 (TL1) login interface in Cisco ONS 15327 4.6(0) and 4.6(1) and 15454 and 15454 SDH 4.6(0) and 4.6(1), when a user account is configured with a blank password, allows remote attackers to gain unauthorized access by logging in with a password larger than 10 characters.

Cisco TelePresence Video Communication Server with software before X7.0.1 allows remote attackers to cause a denial of service (device crash) via a crafted SIP packet, as demonstrated by a SIP INVITE message from a Tandberg device, aka Bug ID CSCtq73319.

Cisco Secure Access Control Server (ACS) 3.2(3) and earlier, when configured with an anonymous bind in Novell Directory Services (NDS) and authenticating NDS users with NDS, allows remote attackers to gain unauthorized access to AAA clients via a blank password.

Cisco EPC3928 devices with EDVA 5.5.10, 5.5.11, and 5.7.1 allow remote attackers to bypass an intended authentication requirement and execute unspecified administrative functions via a crafted HTTP request, aka Bug ID CSCux24941.

Cisco IOS 12.1(3) and 12.1(3)T allows remote attackers to read and modify device configuration data via the cable-docsis read-write community string used by the Data Over Cable Service Interface Specification (DOCSIS) standard.

The Session Initiation Protocol (SIP) implementation in multiple Cisco products including IP Phone models 7940 and 7960, IOS versions in the 12.2 train, and Secure PIX 5.2.9 to 6.2.2 allows remote attackers to cause a denial of service and possibly execute arbitrary code via crafted INVITE messages, as demonstrated by the OUSPG PROTOS c07-sip test suite.

Multiple vulnerabilities in the H.323 protocol implementation for Cisco IOS 11.3T through 12.2T allow remote attackers to cause a denial of service and possibly execute arbitrary code, as demonstrated by the NISCC/OUSPG PROTOS test suite for the H.225 protocol.

Buffer overflow in the authentication module for Cisco ACNS 4.x before 4.2.11, and 5.x before 5.0.5, allows remote attackers to execute arbitrary code via a long password.

Cisco Personal Assistant 1.4(1) and 1.4(2) disables password authentication when "Allow Only Cisco CallManager Users" is enabled and the Corporate Directory settings refer to the directory service being used by Cisco CallManager, which allows remote attackers to gain access with a valid username.

Cisco WebEx Meeting Center does not properly restrict the content of URLs in GET requests, which allows remote attackers to obtain sensitive information or conduct SQL injection attacks via vectors involving read access to a request, aka Bug ID CSCup88398.

Buffer overflow in the HTTP server for Cisco IOS 12.2 and earlier allows remote attackers to execute arbitrary code via an extremely long (2GB) HTTP GET request.

Buffer overflow in Cisco IOS 11.2.x to 12.0.x allows remote attackers to cause a denial of service and possibly execute commands via a large number of OSPF neighbor announcements.

Cisco VPN 3000 series concentrators and Cisco VPN 3002 Hardware Client 3.5.x through 4.0.REL, when enabling IPSec over TCP for a port on the concentrator, allow remote attackers to reach the private network without authentication.

Buffer overflow in the administration service (CSAdmin) for Cisco Secure ACS before 3.1.2 allows remote attackers to cause a denial of service and possibly execute arbitrary code via a long user parameter to port 2002.

Cisco Unity 2.x and 3.x uses well-known default user accounts, which could allow remote attackers to gain access and place arbitrary calls.

Cisco ONS15454 and ONS15327 running ONS before 3.4 allows remote attackers to modify the system configuration and delete files by establishing an FTP connection to the TCC, TCC+ or XTC using a username and password that does not exist.

Check Point Firewall-1 allows remote attackers to bypass port access restrictions on an FTP server by forcing it to send malicious packets that Firewall-1 misinterprets as a valid 227 response to a client's PASV attempt.

Cisco devices running Application and Content Networking System (ACNS) 4.x, 5.0, 5.1, or 5.2 use a default password when the setup dialog has not been run, which allows remote attackers to gain access.

Cisco VPN 3000 Concentrator 2.2.x, and 3.x before 3.5.1, allows restricted administrators to obtain user passwords that are stored in plaintext in HTML source code.

Cisco Virtual Private Network (VPN) Client software 2.x.x, and 3.x before 3.5.2B, does not generate sufficiently random numbers, which may make it vulnerable to certain attacks such as spoofing.

Cisco VPN 3000 Concentrator 2.2.x, and 3.x before 3.5.2, allows restricted administrators to obtain certificate passwords that are stored in plaintext in the HTML source code for Certificate Management pages.

Format string vulnerability in the administration function in Cisco Secure Access Control Server (ACS) for Windows, 2.6.x and earlier and 3.x through 3.01 (build 40), allows remote attackers to crash the CSADMIN module only (denial of service of administration function) or execute arbitrary code via format strings in the URL to port 2002.

The original patch for the Cisco Content Service Switch 11000 Series authentication bypass vulnerability (CVE-2001-0622) was incomplete, which still allows remote attackers to gain additional privileges by directly requesting the web management URL instead of navigating through the interface, possibly via a variant of the original attack, as identified by Cisco bug ID CSCdw08549.

Cross-site scripting vulnerability in CiscoSecure ACS 3.0 allows remote attackers to execute arbitrary script or HTML as other web users via the action argument in a link to setup.exe.

The encryption algorithms for enable and passwd commands on Cisco PIX Firewall can be executed quickly due to a limited number of rounds, which make it easier for an attacker to decrypt the passwords using brute force techniques.

Cisco VPN 3000 Concentrator 3.6(Rel) and earlier, and 2.x.x, when configured to use internal authentication with group accounts and without any user accounts, allows remote VPN clients to log in using PPTP or IPSEC user authentication.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not support the "fragment" keyword in an outgoing ACL, which could allow fragmented packets in violation of the intended access.

Various Intrusion Detection Systems (IDS) including (1) Cisco Secure Intrusion Detection System, (2) Cisco Catalyst 6000 Intrusion Detection System Module, (3) Dragon Sensor 4.x, (4) Snort before 1.8.1, (5) ISS RealSecure Network Sensor 5.x and 6.x before XPU 3.2, and (6) ISS RealSecure Server Sensor 5.5 and 6.0 for Windows, allow remote attackers to evade detection of HTTP attacks via non-standard "%u" Unicode encoding of ASCII characters in the requested URL.

Cisco IOS Firewall Feature set, aka Context Based Access Control (CBAC) or Cisco Secure Integrated Software, for IOS 11.2P through 12.2T does not properly check the IP protocol type, which could allow remote attackers to bypass access control lists.

RSA BSAFE SSL-J 3.0, 3.0.1 and 3.1, as used in Cisco iCND 2.0, caches session IDs from failed login attempts, which could allow remote attackers to bypass SSL client authentication and gain access to sensitive data by logging in after an initial failure.

Cisco 6400 Access Concentrator Node Route Processor 2 (NRP2) 12.1DC card does not properly disable access when a password has not been set for vtys, which allows remote attackers to obtain access via telnet.

Cisco CBOS 2.3.8 and earlier stores the passwords for (1) exec and (2) enable in cleartext in the NVRAM and a configuration file, which could allow unauthorized users to obtain the passwords and gain privileges.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not properly handle the implicit "deny ip any any" rule in an outgoing ACL when the ACL contains exactly 448 entries, which can allow some outgoing packets to bypass access restrictions.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not properly filter does not properly filter packet fragments even when the "fragment" keyword is used in an ACL, which allows remote attackers to bypass the intended access controls.

Cisco switches and routers running CBOS 2.3.8 and earlier use predictable TCP Initial Sequence Numbers (ISN), which allows remote attackers to spoof or hijack TCP connections.

The web management service on Cisco Content Service series 11000 switches (CSS) before WebNS 4.01B29s or WebNS 4.10B17s allows a remote attacker to gain additional privileges by directly requesting the web management URL instead of navigating through the interface.

Cisco Aironet 340 Series wireless bridge before 8.55 does not properly disable access to the web interface, which allows remote attackers to modify its configuration.

Cisco Virtual Central Office 4000 (VCO/4K) uses weak encryption to store usernames and passwords in the SNMP MIB, which allows an attacker who knows the community name to crack the password and gain privileges.

Cisco Prime Network Analysis Module (NAM) before 6.1(1) patch.6.1-2-final and 6.2.x before 6.2(1) and Prime Virtual Network Analysis Module (vNAM) before 6.1(1) patch.6.1-2-final and 6.2.x before 6.2(1) allow remote attackers to execute arbitrary OS commands via a crafted HTTP request, aka Bug ID CSCuy21882.

Cisco routers 9.17 and earlier allow remote attackers to bypass security restrictions via certain IP source routed packets that should normally be denied using the "no ip source-route" command.

The mailguard feature in Cisco Secure PIX Firewall 5.2(2) and earlier does not properly restrict access to SMTP commands, which allows remote attackers to execute restricted commands by sending a DATA command before sending the restricted commands.

Cisco 675 routers running CBOS allow remote attackers to establish telnet sessions if an exec or superuser password has not been set.

Cisco Unity on IBM servers is shipped with default settings that should have been disabled by the manufacturer, which allows local or remote attackers to conduct unauthorized activities via (1) a "bubba" local user account, (2) an open TCP port 34571, or (3) when a local DHCP server is unavailable, a DHCP server on the manufacturer's test network.

Cisco Catalyst 2900 Virtual LAN (VLAN) switches allow remote attackers to inject 802.1q frames into another VLAN by forging the VLAN identifier in the trunking tag.

Vulnerability in Cisco IOS 11.1 through 11.3 with distributed fast switching (DFS) enabled allows remote attackers to bypass certain access control lists when the router switches traffic from a DFS-enabled input interface to an output interface with a logical subinterface, as described by Cisco bug CSCdk43862.

Cisco PIX Private Link 4.1.6 and earlier does not properly process certain commands in the configuration file, which reduces the effective key length of the DES key to 48 bits instead of 56 bits, which makes it easier for an attacker to find the proper key via a brute force attack.

Web Cache Control Protocol (WCCP) in Cisco Cache Engine for Cisco IOS 11.2 and earlier does not use authentication, which allows remote attackers to redirect HTTP traffic to arbitrary hosts via WCCP packets to UDP port 2048.

Cisco IOS 9.1 and earlier does not properly handle extended IP access lists when the IP route cache is enabled and the "established" keyword is set, which could allow attackers to bypass filters.

Some classic Cisco IOS devices have a vulnerability in the PPP CHAP authentication to establish unauthorized PPP connections.