CVE-2026-57819 Apache CXF: No default restriction on the amount of form parameters per message
Attackers can cause denial of service by sending requests with excessive form parameters due to missing default limits in Apache CXF.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-57819?
CVE-2026-57819 is a high-severity denial of service vulnerability in Apache Cxf, published on 6 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-400
Which versions are affected by CVE-2026-57819?
It affects 1 product.
Products include Apache Cxf.
How do I fix CVE-2026-57819?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-57819 being exploited?
There is no known exploitation of CVE-2026-57819 in the wild and no public exploit code.
Other vulnerabilities in Apache Cxf
- CVE-2012-2379 XML Signature/Encryption Not Validated in Apache CXF
- CVE-2026-66909 Apache CXF: Unsafe deserialization of inbound JMS ObjectMessage
- CVE-2026-68079 Apache CXF: DefaultEncryptingCodeDataProvider allows unlimited authorization code replay
- CVE-2026-50628 Apache CXF: OAuth2: Inverted IP Binding Check Defeats Security Control
- CVE-2025-48913 Apache CXF: Untrusted JMS configuration can lead to RCE
Sources
Also known as CLEANSTART-2026-HZ56066, GHSA-rqrh-ghmh-74j5.