VDB
CVE-2026-63384
CVE-2026-63384
PUBLISHED
CVSS 8.7 HIGH
Reported by GitHub_M · Published August 20, 2026
Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has an incorrect integer conversion in event_tagging.c when evtag_unmarshal_header uses evtag_decode_int to decode an attacker-controlled uint32 payload length and returns it as a signed int. Values above INT_MAX become negative or truncated, and evtag_unmarshal_string can use the converted value in allocation sizing, producing a wrapped large allocation request and denial of service. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.
Risk Scores
CVSS 4.0
8.7
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
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| libevent | libevent | >= 2.2.0-alpha, < 2.2.2-alpha, < 2.1.13 |
| libevent | libevent | >= 2.2.0-alpha, < 2.2.2-alpha, < 2.1.13 |
Timeline
- Aug 20, 2026 CVE Published
- Aug 20, 2026 CVE Updated
- Aug 22, 2026 Coalition ESS Score
- Aug 24, 2026 EPSS Score
- Aug 26, 2026 EPSS Score
- Aug 30, 2026 EPSS Score
- Sep 3, 2026 Security Advisory
- Sep 4, 2026 EPSS Score
- Sep 9, 2026 EPSS Score
- Sep 12, 2026 EPSS Score
- Sep 16, 2026 EPSS Score
- Sep 18, 2026 EPSS Score
References
- https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8 x_refsource_CONFIRM
- https://github.com/libevent/libevent/commit/109c16499282959d70f56ec3baf4c8b1e6646bda x_refsource_MISC
- https://github.com/libevent/libevent/commit/5e3c6ebe342b34c5a9bcf48e9a32ad6708b9c416 x_refsource_MISC
- https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable x_refsource_MISC
- https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha x_refsource_MISC