Cisco Firewall Services Module (FWSM) access control list entries (ACEs) security bypass
| cisco-fwsm-ace-security-bypass (37258) |  Medium Risk |
Description:
Cisco Firewall Services Module (FWSM) could allow a remote attacker to bypass security restrictions, caused by an error when loading manipulated ACLs. When deleting and re-adding access control list entries (ACEs), the internal structure of the ACL becomes corrupted, which causes the FWSM to not evaluate some ACEs. A remote attacker could exploit this vulnerability to bypass security restrictions and deny normal traffic while allowing normally restricted traffic.
Platforms Affected:
- Cisco, Firewall Services Module 3.1(5)
- Cisco, Firewall Services Module 3.1(6)
- Cisco, Firewall Services Module 3.2(1)
- Cisco, Firewall Services Module 3.2(2)
Remedy:
Refer to cisco-sa-20071017-fwsm for patch, upgrade or suggested workaround information. See References.
Consequences:
Bypass Security
References:
- cisco-sa-20071017-fwsm, Multiple Vulnerabilities in Firewall Services Module at http://www.cisco.com/warp/public/707/cisco-sa-20071017-fwsm.shtml.
- BID-26109: Cisco Firewall Services Module Multiple DoS and ACL Corruption Vulnerabilities
- CVE-2007-5571: Cisco Firewall Services Module (FWSM) 3.1(6), and 3.2(2) and earlier, does not properly enforce edited ACLs, which might allow remote attackers to bypass intended restrictions on network traffic, aka CSCsj52536.
- SA27236: Cisco FWSM HTTPS/MGCP Packet Processing Denial of Service
- SECTRACK ID: 1018825: Cisco Firewall Service Module HTTPS and MGCP Processing Bugs Let Remote Users Deny Service
- VUPEN/ADV-2007-3530: Cisco Firewall Services Module Remote Denial of Service Vulnerabilities
Reported:
Oct 17, 2007
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