| Name | CVE-2026-63382 |
| Description | 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| libevent (PTS) | bullseye | 2.1.12-stable-1 | vulnerable |
| bookworm | 2.1.12-stable-8 | vulnerable | |
| trixie | 2.1.12-stable-10 | vulnerable | |
| forky, sid | 2.1.13-stable-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| libevent | source | (unstable) | 2.1.13-stable-1 |
https://github.com/libevent/libevent/security/advisories/GHSA-q39v-w2g7-gr8j
Fixed by: https://github.com/libevent/libevent/commit/10abb34b8dc3e1184de315dd261ce4b77563cda6 (release-2.1.13-stable)
Fixed by: https://github.com/libevent/libevent/commit/ac38703b2d312200c4f967f02936af0118d384a0 (release-2.1.13-stable)
Fixed by: https://github.com/libevent/libevent/commit/5119ceb00557bf007f9065709e852686f3c0bb6e (release-2.2.2-alpha)
Fixed by: https://github.com/libevent/libevent/commit/83ba67373032334559b82409db035dd8c3cc1660 (release-2.2.2-alpha)