Bug 2558504 (CVE-2026-111811)

Summary: CVE-2026-111811 trafficserver: Apache Traffic Server: tsmemcache plugin exposes the shared proxy cache over the network with no authentication
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Apache Traffic Server. When the experimental tsmemcache plugin is enabled, it fails to enforce authentication on incoming network connections. An unauthenticated remote attacker can exploit this flaw to inspect, modify, or delete entries in the shared proxy cache, leading to sensitive information disclosure and cache tampering.
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Description OSIDB Bzimport 2026-10-21 19:31:49 UTC 
Apache Traffic Server's experimental tsmemcache plugin allows unauthenticated network read, write, and deletion of the shared proxy cache.



This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.



Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.