Apache CXF up to 3.6.12/4.1.8/4.2.3 Query Parser resource consumption

Summaryinfo

A vulnerability classified as problematic was found in Apache CXF up to 3.6.12/4.1.8/4.2.3. The affected element is an unknown function of the component Query Parser. Executing a manipulation can lead to resource consumption. This vulnerability appears as CVE-2026-86463. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic was found in Apache CXF up to 3.6.12/4.1.8/4.2.3. This vulnerability affects an unknown function of the component Query Parser. The manipulation with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. CVE summarizes:

Apache CXF's FIQL query parser has a vulnerability in how it searches for operators in query expressions. The search pattern can get stuck trying many combinations when it encounters a long string without an operator, causing the parser to consume excessive CPU time. An attacker can send a crafted query to make the server use up CPU resources, potentially slowing down or stopping other requests. The fix was to limit FIQL expressions to 4 KiB by default, preventing attackers from sending extremely long inputs while still allowing normal queries. Users are recommended to upgrade to versions 4.2.4 or 4.1.9 or 3.6.13, which fix this issue.

The advisory is shared for download at lists.apache.org. This vulnerability was named CVE-2026-86463 since 09/07/2026. The exploitation appears to be easy. The attack can be initiated 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 10/09/2026). The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 3.6.13, 4.1.9 or 4.2.4 eliminates this vulnerability.

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Productinfo

Type

• Application Server Software

Vendor

• Apache

Name

• CXF

Version

• 3.6.0
• 3.6.1
• 3.6.2
• 3.6.3
• 3.6.4
• 3.6.5
• 3.6.6
• 3.6.7
• 3.6.8
• 3.6.9
• 3.6.10
• 3.6.11
• 3.6.12
• 4.1.0
• 4.1.1
• 4.1.2
• 4.1.3
• 4.1.4
• 4.1.5
• 4.1.6
• 4.1.7
• 4.1.8
• 4.2.0
• 4.2.1
• 4.2.2
• 4.2.3

License

• open-source

Website

• Vendor: https://www.apache.org/

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