CVE-2026-111814: Apache Traffic Server TLS session reuse with mismatched client certificates

CVE-2026-111814 · Severity: critical · CVSS 10 · Published 2026-10-21

Apache Traffic Server is a high-performance web caching and proxy platform used to accelerate content delivery. A critical vulnerability allows the system to reuse cached TLS connections authenticated with one client certificate to process requests that should use a different certificate, potentially exposing sensitive transactions or enabling unauthorized access to backend services.

Technologies: Apache Traffic Server. Vendors: Apache.

Quick answers

Is CVE-2026-111814 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-111814 being exploited in the wild.
How severe is CVE-2026-111814?
Critical severity, with a CVSS score of 10, published 21 October 2026.
Which products and versions are affected?
Apache Traffic Server 9.0.0 through 9.2.15, 10.0.0 through 10.1.4, 10.2.0.
Is there a fix for CVE-2026-111814?
Yes: fixed in Apache Traffic Server 9.2.16, 10.1.5, 10.2.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-111814 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-111814?
Check whether you run Apache Traffic Server 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

  • Fixed in: Apache Traffic Server 9.2.16, 10.1.5, 10.2.1

Technical details

The vulnerability exists in Traffic Server's default outbound session-sharing policy, which fails to validate that pooled TLS sessions match the client certificate required for each transaction. An attacker can exploit this by sending a request configured to present a different client certificate than the one used to authenticate the pooled session, causing the server to reuse the mismatched session. This affects versions 9.0.0–9.2.15, 10.0.0–10.1.4, and 10.2.0.

Affected products

  • Apache Traffic Server 9.0.0 through 9.2.15, 10.0.0 through 10.1.4, 10.2.0

Timeline

  • 2026-10-21: disclosed

References

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