A vulnerability was found in Cisco IOS 9.1 (Router Operating System). It has been rated as critical. Affected by this issue is some unknown functionality of the component IP Access List Handler. The manipulation with the input value established leads to a privileges management vulnerability. Using CWE to declare the problem leads to CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was disclosed 12/10/1992 as CERT CA-1992-20 as not defined advisory (CERT.org). The advisory is shared for download at cert.org. This vulnerability is handled as CVE-1999-1306. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1068.

Upgrading to version 8.3, 9.0 or 9.1 eliminates this vulnerability. It is possible to mitigate the problem by applying the configuration setting no ip route-cache. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The entry 13653 is pretty similar.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• IOS

Version

• 9.1

License

• commercial

Support

• end of life (old version)

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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