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CVE-2026-111817

Apache Traffic Server: Dropping chunked trailers stalls a passthrough transfer until timeout

Apache Software Foundation Apache Traffic Server
Open in ThreatlineRecord JSON
CVSS
5.3Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.26%Chance of exploitation activity in the next 30 days, higher than 17% 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 can stall a chunked transfer that it passes through with its trailers removed (proxy.config.http.drop_chunked_trailers) until the connection times out, because it waits for the trailer bytes it has already dropped. Trailer dropping is on by default in 10.x. In 8.1.11 and 9.2.x it is off by default, and those versions are affected only if it is enabled.

This issue affects Apache Traffic Server: 8.1.11, from 9.2.5 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.

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

Text from CVE List

Affected versions 4

  • Apache Traffic Serveraffected: 8.1.11CVE List
  • Apache Traffic Serveraffected: 9.2.5 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