Vulnerabilities (CVE)

The Cisco Optical Service Module (OSM) for the Catalyst 6500 and 7600 series running Cisco IOS 12.1(8)E through 12.1(13.4)E allows remote attackers to cause a denial of service (hang) via a malformed packet.

Cisco IOS 12.0 through 12.3YL, with BGP enabled and running the bgp log-neighbor-changes command, allows remote attackers to cause a denial of service (device reload) via a malformed BGP packet.

The VLAN Trunking Protocol (VTP) feature in Cisco IOS 12.1(19) allows remote attackers to cause a denial of service by sending a VTP version 1 summary frame with a VTP version field value of 2.

Cisco Gigabit Switch Routers (GSR) with Fast Ethernet / Gigabit Ethernet cards, from IOS versions 11.2(15)GS1A up to 11.2(19)GS0.2 and some versions of 12.0, do not properly handle line card failures, which allows remote attackers to bypass ACLs or force the interface to stop forwarding packets.

Heap-based buffer overflow in the VLAN Trunking Protocol (VTP) feature in Cisco IOS 12.1(19) allows remote attackers to execute arbitrary code via a long VLAN name in a VTP type 2 summary advertisement.

Cisco IOS 12.0, 12.1, and 12.2, when GRE IP tunneling is used and the RFC2784 compliance fixes are missing, does not verify the offset field of a GRE packet during decapsulation, which leads to an integer overflow that references data from incorrect memory locations, which allows remote attackers to inject crafted packets into the routing queue, possibly bypassing intended router ACLs.

Vulnerability in Cisco routers versions 8.2 through 9.1 allows remote attackers to bypass access control lists when extended IP access lists are used on certain interfaces, the IP route cache is enabled, and the access list uses the "established" keyword.

Cisco IOS 12.1(2)T, 12.1(3)T allow remote attackers to cause a denial of service (reload) via a connection to TCP ports 3100-3999, 5100-5999, 7100-7999 and 10100-10999.

Cross-site scripting (XSS) vulnerability in Cisco IOS Web Server for IOS 12.0(2a) allows remote attackers to inject arbitrary web script or HTML by (1) packets containing HTML that an administrator views via an HTTP interface to the contents of memory buffers, as demonstrated by the URI /level/15/exec/-/buffers/assigned/dump; or (2) sending the router Cisco Discovery Protocol (CDP) packets with HTML payload that an administrator views via the CDP status pages. NOTE: these vectors were originall ... Cross-site scripting (XSS) vulnerability in Cisco IOS Web Server for IOS 12.0(2a) allows remote attackers to inject arbitrary web script or HTML by (1) packets containing HTML that an administrator views via an HTTP interface to the contents of memory buffers, as demonstrated by the URI /level/15/exec/-/buffers/assigned/dump; or (2) sending the router Cisco Discovery Protocol (CDP) packets with HTML payload that an administrator views via the CDP status pages. NOTE: these vectors were originally reported as being associated with the dump and packet options in /level/15/exec/-/show/buffers.

Show More

Cisco IOS software 11.3 through 12.2 running on Cisco uBR7200 and uBR7100 series Universal Broadband Routers allows remote attackers to modify Data Over Cable Service Interface Specification (DOCSIS) settings via a DOCSIS file without a Message Integrity Check (MIC) signature, which is approved by the router.

Multiple SSH2 servers and clients do not properly handle packets or data elements with incorrect length specifiers, which may allow remote attackers to cause a denial of service or possibly execute arbitrary code, as demonstrated by the SSHredder SSH protocol test suite.

Multiple SSH2 servers and clients do not properly handle large packets or large fields, which may allow remote attackers to cause a denial of service or possibly execute arbitrary code via buffer overflow attacks, as demonstrated by the SSHredder SSH protocol test suite.

Cisco IOS 12.2T, 12.3 and 12.3T, when processing an ISAKMP profile that specifies XAUTH authentication after Phase 1 negotiation, may not process certain attributes in the ISAKMP profile that specifies XAUTH, which allows remote attackers to bypass XAUTH and move to Phase 2 negotiations.

The TCL shell in Cisco IOS 12.2(14)S before 12.2(14)S16, 12.2(18)S before 12.2(18)S11, and certain other releases before 25 January 2006 does not perform Authentication, Authorization, and Accounting (AAA) command authorization checks, which may allow local users to execute IOS EXEC commands that were prohibited via the AAA configuration, aka Bug ID CSCeh73049.

The VLAN Trunking Protocol (VTP) feature in Cisco IOS 12.1(19) and CatOS allows remote attackers to cause a denial of service by sending a VTP update with a revision value of 0x7FFFFFFF, which is incremented to 0x80000000 and is interpreted as a negative number in a signed context.

Cisco IOS 12.2 and earlier generates a "% Login invalid" message instead of prompting for a password when an invalid username is provided, which allows remote attackers to identify valid usernames on the system and conduct brute force password guessing, as reported for the Aironet Bridge.

The design of the Hot Standby Routing Protocol (HSRP), as implemented on Cisco IOS 12.1, when using IRPAS, allows remote attackers to cause a denial of service (CPU consumption) via a router with the same IP address as the interface on which HSRP is running, which causes a loop.

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.

Cisco IOS 12.0 through 12.2, when IP routing is disabled, accepts false ICMP redirect messages, which allows remote attackers to cause a denial of service (network routing modification).

Heap-based buffer overflow in the TFTP server capability in Cisco IOS 11.1, 11.2, and 11.3 allows remote attackers to cause a denial of service (reset) or modify configuration via a long filename.

Cisco IOS 12.0S, 12.2, and 12.3, with Open Shortest Path First (OSPF) enabled, allows remote attackers to cause a denial of service (device reload) via a malformed OSPF packet.

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.

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.

Cisco switches and routers running IOS 12.1 and earlier produce predictable TCP Initial Sequence Numbers (ISNs), which allows remote attackers to spoof or hijack TCP connections.

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.

The "established" keyword in some Cisco IOS software allowed an attacker to bypass filtering.

Cisco IOS 11.1(x) through 11.3(x) and 12.0(x) through 12.2(x), when configured for BGP routing, allows remote attackers to cause a denial of service (device reload) via malformed BGP (1) OPEN or (2) UPDATE messages.

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.

Cisco IOS 12.0 through 12.4 and IOS XR before 3.2, with IPv6 enabled, allows remote attackers on a local network segment to cause a denial of service (device reload) and possibly execute arbitrary code via a crafted IPv6 packet.

Cisco IOS 12.0 and other versions can be crashed by malicious UDP packets to the syslog port.

OpenSSL 0.9.6 before 0.9.6d does not properly handle unknown message types, which allows remote attackers to cause a denial of service (infinite loop), as demonstrated using the Codenomicon TLS Test Tool.

Cisco IOS 2.2(18)EW, 12.2(18)EWA, 12.2(14)SZ, 12.2(18)S, 12.2(18)SE, 12.2(18)SV, 12.2(18)SW, and other versions without the "no service dhcp" command, keep undeliverable DHCP packets in the queue instead of dropping them, which allows remote attackers to cause a denial of service (dropped traffic) via multiple undeliverable DHCP packets that exceed the input queue size.

Cisco IOS 11.x and 12.x allows remote attackers to cause a denial of service by sending the ENVIRON option to the Telnet daemon before it is ready to accept it, which causes the system to reboot.

PPTP implementation in Cisco IOS 12.1 and 12.2 allows remote attackers to cause a denial of service (crash) via a malformed packet.

Cisco Internetwork Operating System (IOS) 12.0S through 12.3T attempts to process SNMP solicited operations on improper ports (UDP 162 and a randomly chosen UDP port), which allows remote attackers to cause a denial of service (device reload and memory corruption).

Land IP denial of service.

Cisco IOS 11.2.x and 12.0.x does not limit the size of its redirect table, which allows remote attackers to cause a denial of service (memory consumption) via spoofed ICMP redirect packets to the router.

Buffer overflow in Cisco TACACS+ tac_plus server allows remote attackers to cause a denial of service via a malformed packet with a long length field.

Secure Shell (SSH) 2 in Cisco IOS 12.0 through 12.3 allows remote attackers to cause a denial of service (device reload) (1) via a username that contains a domain name when using a TACACS+ server to authenticate, (2) when a new SSH session is in the login phase and a currently logged in user issues a send command, or (3) when IOS is logging messages and an SSH session is terminated while the server is sending data.

Certain Cisco IOS releases in 12.2S based trains with maintenance release number 25 and later, 12.3T based trains, and 12.4 based trains reuse a Tcl Shell process across login sessions of different local users on the same terminal if the first user does not use tclquit before exiting, which may cause subsequent local users to execute unintended commands or bypass AAA command authorization checks, aka Bug ID CSCef77770.