---
id: CVE-2026-111817
title: >-
  Apache Traffic Server: Dropping chunked trailers stalls a passthrough transfer
  until timeout
summary: >-
  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. …
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cvssSource: cna
cwe:
  - CWE-400
vendor: Apache Software Foundation
product: Apache Traffic Server
affected:
  - apache_traffic_server 8.1.11
  - apache_traffic_server >= 9.2.5 <= 9.2.15
  - apache_traffic_server >= 10.0.0 <= 10.1.4
  - apache_traffic_server 10.2.0
published: '2026-10-21'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T19:20:00.515Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-111817'
references:
  - url: 'https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc'
tags:
  - cve.org
ingestedAt: '2026-10-21T20:11:44.908Z'
---

## Overview

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.

## Affected

- `apache_traffic_server 8.1.11`
- `apache_traffic_server >= 9.2.5 <= 9.2.15`
- `apache_traffic_server >= 10.0.0 <= 10.1.4`
- `apache_traffic_server 10.2.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.