CVE-2026-63383
Libevent: decode_tag_internal() can lead to out-of-bounds read
- State
- Published
- Severity
- 8.7 High
- Published
- Aug 20, 2026
- Updated
- Aug 20, 2026
- Reserved
- Jul 16, 2026
Description
Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent can read beyond a contiguous evbuffer region in event_tagging.c when decode_tag_internal requests at most five bytes from evbuffer_pullup but iterates using the full logical buffer length. A fragmented evbuffer containing a six-byte malformed tag can therefore advance past the pullup window and trigger an out-of-bounds read, which can crash a process that decodes attacker-controlled tagged RPC data. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 8.7 High | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-125 Out-of-bounds Read
Affected Products
| Product | Versions |
|---|---|
libeventlibevent |
|
References
- https://github.com/libevent/libevent/security/advisories/GHSA-fj29-64w6-73h6
- https://github.com/libevent/libevent/commit/91ed8745eebabdd27592a83d350338a8c4626321
- https://github.com/libevent/libevent/commit/e1f9e21887c6b104e206a718385ba3ffc75180cb
- https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable
- https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
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