CVE-2026-57819: Apache CXF: No default restriction on the amount of form parameters per message

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-06 · updated 2026-10-24
Weakness: CWE-400

Description

Apache CXF allows to set a limit on the number of form parameters in a JAX-RS message via the "maxFormParameterCount" configuration option. However, no default limit is set which may lead to denial of service attacks when processing requests with very large numbers of form parameters. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue by using a default limit of 500 parameters.

Affected products

Apache Software Foundation Apache CXF: before 3.6.12; from 4.0.0 before 4.1.8; from 4.2.0 before 4.2.3 — fixed in 3.6.12, 4.1.8, 4.2.3

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache CXF 3.6.12, 4.1.8, 4.2.3. Check the vendor advisory for mitigations.

References

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