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 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.

Cisco IOS 12.0S through 12.3YH allows remote attackers to cause a denial of service (device restart) via a crafted IPv6 packet.

Cisco Catalyst 6000, 5000, or 4000 switches allow remote attackers to cause a denial of service by connecting to the SSH service with a non-SSH client, which generates a protocol mismatch error.

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.

Cisco IOS 12.1YD, 12.2T, 12.3 and 12.3T, when configured for the IOS Telephony Service (ITS), CallManager Express (CME) or Survivable Remote Site Telephony (SRST), allows remote attackers to cause a denial of service (device reboot) via a malformed packet to the SCCP port.

Cisco Virtual Private Network (VPN) Client 3.5.4 and earlier allows remote attackers to cause a denial of service (CPU consumption) via a packet with a zero-length payload.

In Cisco routers under some versions of IOS 12.0 running NAT, some packets may not be filtered by input access list filters.

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.

Cisco VACM (View-based Access Control MIB) for Catalyst Operating Software (CatOS) 5.5 and 6.1 and IOS 12.0 and 12.1 allows remote attackers to read and modify device configuration via the read-write community string.

Buffer overflows in Cisco Virtual Private Network (VPN) Client 3.5.4 and earlier allows remote attackers to cause a denial of service via (1) an Internet Key Exchange (IKE) with a large Security Parameter Index (SPI) payload, or (2) an IKE packet with a large number of valid payloads.

The default installation of Cisco voice products, when running the IBM Director Agent on IBM servers before OS 2000.2.6, does not require authentication, which allows remote attackers to gain administrator privileges by connecting to TCP port 14247.

The Web interface to Cisco 600 routers running CBOS 2.4.1 and earlier allow remote attackers to cause a denial of service via a URL that does not end in a space character.

Cisco voice products, when running the IBM Director Agent on IBM servers before OS 2000.2.6, allows remote attackers to cause a denial of service (CPU consumption) via arbitrary packets to TCP port 14247, as demonstrated using port scanning.

Linux-iSCSI iSCSI implementation installs the iscsi.conf file with world-readable permissions on some operating systems, including Red Hat Linux Limbo Beta #1, which could allow local users to gain privileges by reading the cleartext CHAP password.

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.

Cisco VPN 5000 series concentrator hardware 6.0.21.0002 and earlier, and 5.2.23.0003 and earlier, when using RADIUS with a challenge type of Password Authentication Protocol (PAP) or Challenge, sends the user password in cleartext in a validation retry request, which could allow remote attackers to steal passwords via sniffing.

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 600 routers running CBOS 2.4.1 and earlier allow remote attackers to cause a denial of service via a large ICMP echo (ping) packet.

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.