Apache Traffic Server up to 9.2.10/10.0.5 Proxy Protocol access control

Summaryinfo

A vulnerability described as critical has been identified in Apache Traffic Server up to 9.2.10/10.0.5. Affected is an unknown function of the component Proxy Protocol Handler. The manipulation results in access control. This vulnerability was named CVE-2025-31698. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Apache Traffic Server up to 9.2.10/10.0.5. It has been classified as critical. Affected is an unknown code block of the component Proxy Protocol Handler. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

ACL configured in ip_allow.config or remap.config does not use IP addresses that are provided by PROXY protocol. Users can use a new setting (proxy.config.acl.subjects) to choose which IP addresses to use for the ACL if Apache Traffic Server is configured to accept PROXY protocol.  This issue affects undefined: from 10.0.0 through 10.0.6, from 9.0.0 through 9.2.10. Users are recommended to upgrade to version 9.2.11 or 10.0.6, which fixes the issue.

The advisory is shared for download at seclists.org. This vulnerability is traded as CVE-2025-31698. The exploitability is told to be easy. It is possible to launch the attack remotely. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/26/2025). The MITRE ATT&CK project declares the attack technique as T1068.

The vulnerability scanner Nessus provides a plugin with the ID 240505 (Debian dsa-5948 : trafficserver - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 9.2.11 or 10.0.6 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (240505). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• Apache

Name

• Traffic Server

Version

• 9.2.0
• 9.2.1
• 9.2.2
• 9.2.3
• 9.2.4
• 9.2.5
• 9.2.6
• 9.2.7
• 9.2.8
• 9.2.9
• 9.2.10
• 10.0.0
• 10.0.1
• 10.0.2
• 10.0.3
• 10.0.4
• 10.0.5

License

• open-source

Website

• Vendor: https://www.apache.org/

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Once again VulDB remains the best source for vulnerability data.

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