CVE-2026-111805 Apache Software Foundation CVE debrief

Who should care

System administrators and security teams responsible for Apache Traffic Server deployments should assess exposure and verify worker pool exhaustion via truncated HTTP/2 Content-Length values.

Why it matters

Defenders should prioritize upgrading Apache Traffic Server to version 9.2.16, 10.1.5, or 10.2.1. System administrators and security teams responsible for Apache Traffic Server deployments should assess exposure and verify worker pool exhaustion via truncated HTTP/2 Content-Length values. The CVE record and source item provide details on the vulnerability, affected versions, and recommended upgrades. However, limited information is available on potential exploitation or specific attack scenarios.

• Verify worker pool exhaustion via truncated HTTP/2 Content-Length values
• Assess exposure of Apache Traffic Server deployments
• Prioritize upgrading to version 9.2.16, 10.1.5, or 10.2.1

Technical summary

Apache Traffic Server can be used to exhaust an HTTP/1.1 origin's worker pool via a truncated HTTP/2 Content-Length value. 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. The vulnerability allows a client to trigger backend worker-pool exhaustion. Defenders should prioritize upgrading Apache Traffic Server to version 9.2.16, 10.1.5, or 10.2.1. System administrators and security teams responsible for Apache Traffic Server deployments should assess exposure and verify worker pool exhaustion via truncated HTTP/2 Content-Length values.

Defensive priority

Defenders should prioritize upgrading Apache Traffic Server to version 9.2.16, 10.1.5, or 10.2.1. System administrators and security teams responsible for Apache Traffic Server deployments should assess exposure and verify worker pool exhaustion via truncated HTTP/2 Content-Length values.

Recommended defensive actions

• Upgrade Apache Traffic Server to version 9.2.16, 10.1.5, or 10.2.1
• Assess exposure and verify worker pool exhaustion via truncated HTTP/2 Content-Length values
• Monitor Apache Traffic Server deployments for potential worker pool exhaustion
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on the vulnerability, affected versions, and recommended upgrades. However, limited information is available on potential exploitation or specific attack scenarios.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.