critical · 9.1 Patched

Apache Tomcat util accepted misconfigured CRLs

CVE-2026-53434 · GHSA-4x29-79gh-6v8q · BIT-tomcat-2026-53434 · published 29 Jun 2026

How serious is it

  • Severity: critical, CVSS score 9.1 out of 10.
  • No exploit prediction (EPSS) score yet.
  • Not on the CISA list of exploited vulnerabilities.
  • No public exploit in Exploit-DB.

Is your app affected by CVE-2026-53434?

Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.

Who is affected

  • org.apache.tomcat:tomcat-util (Maven) >= 11.0.0-M1, <= 11.0.22
  • org.apache.tomcat:tomcat-util (Maven) >= 10.1.0-M7, <= 10.1.55
  • org.apache.tomcat:tomcat-util (Maven) >= 9.0.83, <= 9.0.118

How to check

  1. Look for org.apache.tomcat:tomcat-util in your lockfile and compare its version with the range above.
  2. Or paste your lockfile into the checker: it lists every package with a known vulnerability, this one included.

How to fix

Copies a prompt for Claude Code, Cursor or Codex: it checks your lockfiles for this and upgrades it.
  1. On >= 11.0.0-M1, <= 11.0.22: Upgrade org.apache.tomcat:tomcat-util to 11.0.23 or later, commit the lockfile and redeploy.
  2. On >= 10.1.0-M7, <= 10.1.55: Upgrade org.apache.tomcat:tomcat-util to 10.1.56 or later, commit the lockfile and redeploy.
  3. On >= 9.0.83, <= 9.0.118: Upgrade org.apache.tomcat:tomcat-util to 9.0.119 or later, commit the lockfile and redeploy.
  4. If a vulnerable version was live, check your logs and rotate the secrets that server could read.

The advisory

Detection of Error Condition Without Action vulnerability in Apache Tomcat when configuring Certificate Revocation List (CRLs) for a FFM based connector. If an FFM connector was configured with invalid CRLs, the invalid CRLs were ignored meaning invalid certificates could be accepted. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M7 through 10.1.55, from 9.0.83 through 9.0.118. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fixes the issue.

Check your whole app

Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.

References

Merged from GitHub Advisory Database, OSV. Last updated 26 Oct 2026. All vulnerabilities · RSS · JSON

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