Cisco IOS before 15.0(1)XA1, when certain TFTP debugging is enabled, allows remote attackers to cause a denial of service (device crash) via a TFTP copy over IPv6, aka Bug ID CSCtb28877.

Memory leak in Cisco IOS before 15.0(1)XA5 might allow remote attackers to cause a denial of service (memory consumption) by sending a crafted SIP REGISTER message over UDP, aka Bug ID CSCtg41733.

CallManager Express (CME) on Cisco IOS before 15.0(1)XA allows remote authenticated users to cause a denial of service (device crash) by using an extension mobility (EM) phone to interact with the menu for SNR number changes, aka Bug ID CSCta63555.

Memory leak in the gk_circuit_info_do_in_acf function in the H.323 implementation in Cisco IOS before 15.0(1)XA allows remote attackers to cause a denial of service (memory consumption) via a large number of calls over a long duration, as demonstrated by InterZone Clear Token (IZCT) test traffic, aka Bug ID CSCsz72535.

Cisco IOS before 15.0(1)XA does not properly handle IRC traffic during a specific time period after an initial reload, which allows remote attackers to cause a denial of service (device reload) via an attempted connection to a certain IRC server, related to a "corrupted magic value," aka Bug ID CSCso05336.

The Neighbor Discovery (ND) protocol implementation in the IPv6 stack in Cisco IOS before 15.0(1)XA5 allows remote attackers to cause a denial of service (CPU consumption and device hang) by sending many Router Advertisement (RA) messages with different source addresses, as demonstrated by the flood_router6 program in the thc-ipv6 package, aka Bug ID CSCti33534.

The TCP implementation in (1) Linux, (2) platforms based on BSD Unix, (3) Microsoft Windows, (4) Cisco products, and probably other operating systems allows remote attackers to cause a denial of service (connection queue exhaustion) via multiple vectors that manipulate information in the TCP state table, as demonstrated by sockstress.

The virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (resource exhaustion) via a series of PPTP sessions, related to the persistence of interface descriptor block (IDB) data structures after process termination, aka bug ID CSCdv59309.

Memory leak in the virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (memory consumption) via a series of PPTP sessions, related to "dead memory" that remains allocated after process termination, aka bug ID CSCsj58566.

Stack-based buffer overflow in the Line Printer Daemon (LPD) in Cisco IOS before 12.2(18)SXF11, 12.4(16a), and 12.4(2)T6 allow remote attackers to execute arbitrary code by setting a long hostname on the target system, then causing an error message to be printed, as demonstrated by a telnet session to the LPD from a source port other than 515.

The Data-link Switching (DLSw) feature in Cisco IOS 11.0 through 12.4 allows remote attackers to cause a denial of service (device reload) via "an invalid value in a DLSw message... during the capabilities exchange."

Cisco IOS 12.2 through 12.4 before 20060920, as used by Cisco IAD2430, IAD2431, and IAD2432 Integrated Access Devices, the VG224 Analog Phone Gateway, and the MWR 1900 and 1941 Mobile Wireless Edge Routers, is incorrectly identified as supporting DOCSIS, which allows remote attackers to gain read-write access via a hard-coded cable-docsis community string and read or modify arbitrary SNMP variables.

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.

Cisco IOS 12.2(15) and earlier allows remote attackers to cause a denial of service (refused VTY (virtual terminal) connections), via a crafted TCP connection to the Telnet or reverse Telnet port.

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 11.x and 12.0 through 12.2 allows remote attackers to cause a denial of service (traffic block) by sending a particular sequence of IPv4 packets to an interface on the device, causing the input queue on that interface to be marked as full.

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 devices IOS 12.0 and earlier allow a remote attacker to cause a crash, or bad route updates, via malformed BGP updates with unrecognized transitive attribute.

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.