CVE-2026-29129: Configured cipher preference order not preserved vulnerability in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.16 through 11.

CVE-2026-29129 · Severity: high · CVSS 7.5 · Published 2026-04-09

Apache Tomcat is a widely used web server and application container for Java-based websites. A vulnerability was identified where the server fails to respect the security administrator's preferred order of encryption methods (ciphers). This could allow a connection to use a weaker encryption method than intended, potentially exposing sensitive data to interception.

Technologies: Apache Tomcat, org.apache.tomcat:tomcat (Maven), org.apache.tomcat:tomcat-coyote (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven). Vendors: Apache, Maven.

Quick answers

Is CVE-2026-29129 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-29129 being exploited in the wild.
How severe is CVE-2026-29129?
High severity, with a CVSS score of 7.5, published 9 April 2026.
Which products and versions are affected?
Apache Tomcat 11.0.16 to 11.0.18, 10.1.51 to 10.1.52, 9.0.114 to 9.0.115, 9.0.114 to 9.0.115, 10.1.51 to 10.1.52, 11.0.16 to 11.0.18; org.apache.tomcat:tomcat (Maven) ECOSYSTEM:introduced=9.0.114,fixed=9.0.116; org.apache.tomcat:tomcat-coyote (Maven) ECOSYSTEM:introduced=9.0.114,fixed=9.0.116; org.apache.tomcat.embed:tomcat-embed-core (Maven) ECOSYSTEM:introduced=9.0.114,fixed=9.0.116.
Is there a fix for CVE-2026-29129?
Yes. org.apache.tomcat:tomcat (Maven): upgrade to 9.0.116 or later; org.apache.tomcat:tomcat-coyote (Maven): upgrade to 9.0.116 or later; org.apache.tomcat.embed:tomcat-embed-core (Maven): upgrade to 9.0.116 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-29129 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-29129?
Check whether you run Apache Tomcat, org.apache.tomcat:tomcat (Maven), org.apache.tomcat:tomcat-coyote (Maven) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • org.apache.tomcat:tomcat (Maven): upgrade to 9.0.116 or later
    # set org.apache.tomcat:tomcat to 9.0.116 in your pom.xml or build.gradle
  • org.apache.tomcat:tomcat-coyote (Maven): upgrade to 9.0.116 or later
    # set org.apache.tomcat:tomcat-coyote to 9.0.116 in your pom.xml or build.gradle
  • org.apache.tomcat.embed:tomcat-embed-core (Maven): upgrade to 9.0.116 or later
    # set org.apache.tomcat.embed:tomcat-embed-core to 9.0.116 in your pom.xml or build.gradle

Technical details

A vulnerability in Apache Tomcat (CWE-327) occurs because the server does not preserve the configured cipher preference order during the TLS handshake. This issue affects Tomcat versions 11.0.16-11.0.18, 10.1.51-10.1.52, and 9.0.114-9.0.115. An unauthenticated remote attacker can exploit this by negotiating a connection using a weaker cipher than the administrator intended, even if stronger ciphers are available and prioritized in the configuration. This can lead to a loss of confidentiality if the negotiated cipher is susceptible to known cryptographic attacks. The issue is resolved in versions 11.0.20, 10.1.53, and 9.0.116.

Affected products

  • Apache Tomcat 9.0.114 to 9.0.115, 10.1.51 to 10.1.52, 11.0.16 to 11.0.18

Identifiers

  • CVE-2026-29129
  • GHSA-69cc-cv78-qc8g

Timeline

  • 2026-04-09: disclosed
  • 2026-04-09: advisory
  • 2026-04-10: other: GitHub advisory reviewed

References

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