All vulnerabilities
CVE-2026-111816

Apache Traffic Server: A malformed 302 response bypasses parse-error rejection through the Transfer-Encoding: chunked carve-out

Apache Software Foundation Apache Traffic Server
Open in ThreatlineRecord JSON
CVSS
9.3Critical
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.24%Chance of exploitation activity in the next 30 days, higher than 13% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Published21 Oct 2026Updated 23 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Description

Apache Traffic Server forwarded a malformed 302 response that should have been rejected as a parse error, because the Transfer-Encoding: chunked carve-out bypassed the rejection path. A response that two peers can read differently is then stored and served, allowing cache poisoning and response-framing desync.

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.

Text from CVE List

Affected versions 4

  • Apache Traffic Serveraffected: 8.0.0 through 8.1.11CVE List
  • Apache Traffic Serveraffected: 9.0.0 through 9.2.15CVE List
  • Apache Traffic Serveraffected: 10.0.0 through 10.1.4CVE List
  • Apache Traffic Serveraffected: 10.2.0CVE List

References 1