# CVE-2026-24734: Apache Tomcat certificate revocation bypass in OCSP validation

Source: https://junglewise.ai/threats/cve-2026-24734-apache-tomcat-certificate-revocation-bypass-in-ocsp-validation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-02-17. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-24734 · Severity: high · CVSS 7.5 · Published 2026-02-17

Apache Tomcat, a widely used web server for Java applications, contains a security flaw in how it verifies digital certificates. When checking if a certificate has been cancelled (revoked), the system fails to properly validate the response from the verification service. This could allow an attacker to use a stolen or invalid certificate to gain unauthorized access to secure systems, potentially compromising sensitive data or operations.

Technologies: [org.apache.tomcat:tomcat-coyote (Maven)](https://junglewise.ai/threats/technologies/org-apache-tomcat-tomcat-coyote), [org.apache.tomcat:tomcat-coyote-ffm (Maven)](https://junglewise.ai/threats/technologies/org-apache-tomcat-tomcat-coyote-ffm), [org.apache.tomcat.embed:tomcat-embed-core (Maven)](https://junglewise.ai/threats/technologies/org-apache-tomcat-embed-tomcat-embed-core). Vendors: [Apache Software Foundation](https://junglewise.ai/threats/vendors/apache-software-foundation), [Maven](https://junglewise.ai/threats/vendors/maven), [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-24734 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-24734 being exploited in the wild.

**How severe is CVE-2026-24734?** High severity, with a CVSS score of 7.5, published 17 February 2026.

**Which products and versions are affected?** Apache Software Foundation Tomcat Native 1.3.0 through 1.3.4, 2.0.0 through 2.0.11, 1.1.23 through 1.1.34, 1.2.0 through 1.2.39; org.apache.tomcat:tomcat-coyote (Maven) >= 11.0.0-M1, < 11.0.18, ECOSYSTEM:introduced=11.0.0-M1,fixed=11.0.18; org.apache.tomcat:tomcat-coyote-ffm (Maven) >= 11.0.0-M1, < 11.0.18; org.apache.tomcat.embed:tomcat-embed-core (Maven) >= 11.0.0-M1, < 11.0.18, ECOSYSTEM:introduced=11.0.0-M1,fixed=11.0.18; and 1 more.

**Is there a fix for CVE-2026-24734?** Yes. org.apache.tomcat:tomcat-coyote (Maven): upgrade to 11.0.18 or later; org.apache.tomcat.embed:tomcat-embed-core (Maven): upgrade to 11.0.18 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-24734 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-24734?** Check whether you run Apache Software Foundation Tomcat Native, org.apache.tomcat:tomcat-coyote (Maven), org.apache.tomcat:tomcat-coyote-ffm (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-coyote (Maven): upgrade to 11.0.18 or later

  ```sh
  # set org.apache.tomcat:tomcat-coyote to 11.0.18 in your pom.xml or build.gradle
  ```

- org.apache.tomcat.embed:tomcat-embed-core (Maven): upgrade to 11.0.18 or later

  ```sh
  # set org.apache.tomcat.embed:tomcat-embed-core to 11.0.18 in your pom.xml or build.gradle
  ```


## Technical details

An improper input validation vulnerability exists in Apache Tomcat Native and the FFM port of Tomcat Native code. The flaw occurs during the processing of Online Certificate Status Protocol (OCSP) responses, where the software fails to complete necessary verification or freshness checks. A remote, unauthenticated attacker can exploit this by providing a specially crafted or stale OCSP response, effectively bypassing certificate revocation lists. This allows the use of revoked certificates for TLS authentication. Patches are available in Tomcat versions 11.0.18, 10.1.52, and 9.0.115, and Tomcat Native versions 1.3.5 and 2.0.12.

## Affected products

- Apache Tomcat Native 1.3.0 through 1.3.4, 2.0.0 through 2.0.11, 1.1.23 through 1.1.34, 1.2.0 through 1.2.39
- Apache Tomcat 11.0.0-M1 through 11.0.17, 10.1.0-M7 through 10.1.51, 9.0.83 through 9.0.114
- Red Hat JBoss Web Server 5, 6.2
- Red Hat Enterprise Linux 9, 10

## Identifiers

- CVE-2026-24734
- GHSA-mgp5-rv84-w37q

## Timeline

- 2026-02-17: advisory: Initial NVD publication date
- 2026-05-19: patched: Red Hat released security updates for RHEL 10
- 2026-06-16: patched: Red Hat released security updates for RHEL 9

## References

- [https://lists.apache.org/thread/292dlmx3fz1888v6v16221kpozq56gml](https://lists.apache.org/thread/292dlmx3fz1888v6v16221kpozq56gml)
- [https://access.redhat.com/errata/RHSA-2026:19054](https://access.redhat.com/errata/RHSA-2026:19054)
- [https://access.redhat.com/errata/RHSA-2026:26323](https://access.redhat.com/errata/RHSA-2026:26323)
- [https://access.redhat.com/errata/RHSA-2026:5611](https://access.redhat.com/errata/RHSA-2026:5611)
- [https://access.redhat.com/errata/RHSA-2026:5612](https://access.redhat.com/errata/RHSA-2026:5612)
- [https://access.redhat.com/errata/RHSA-2026:6569](https://access.redhat.com/errata/RHSA-2026:6569)
- [https://access.redhat.com/errata/RHSA-2026:8334](https://access.redhat.com/errata/RHSA-2026:8334)

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