Description
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.
References6
- github.com/libevent/libevent/commit/109c16499282959d70f56ec3baf…
- github.com/libevent/libevent/commit/5e3c6ebe342b34c5a9bcf48e9a3…
- github.com/libevent/libevent/releases/tag/release-2.1.13-stable
- github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
- github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49…
- github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49…
Metrics
- CVSS 4.0
-
8.7
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 42 · as of 10 November 2026
- CWE
- CWE-190
Could this be exploited in your environment?
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