HTTP Request Smuggling Affecting libevent-devel package, versions *


Severity

Recommended
0.0
high
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.78% (55th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-CENTOS6-LIBEVENTDEVEL-19773183
  • published13 Sept 2026
  • disclosed20 Aug 2026

Introduced: 20 Aug 2026

CVE-2026-63382  (opens in a new tab)
CWE-444  (opens in a new tab)

How to fix?

There is no fixed version for Centos:6 libevent-devel.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libevent-devel package and not the libevent-devel package as distributed by Centos. See How to fix? for Centos:6 relevant fixed versions and status.

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, the libevent evhttp parser in http.c inconsistently handles duplicate Transfer-Encoding headers, comma-separated Transfer-Encoding values, and bare line feeds in chunked framing. evhttp_find_header can select only the first header, evhttp_check_transfer_encoding_ was absent so the previous whole-string comparison fails to recognize valid lists ending in chunked, and evhttp_handle_chunked_read uses EVBUFFER_EOL_CRLF rather than EVBUFFER_EOL_CRLF_STRICT, accepting bare LF chunk terminators. When libevent is deployed behind a proxy that frames the same request differently, an unauthenticated remote attacker can desynchronize request boundaries and smuggle a second request, potentially bypassing access controls or poisoning caches. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

CVSS Base Scores

version 3.1