CVE-2026-63384CWE-190

CVE-2026-63384

published August 20, 2026

CVSS
8.7
EPSS
1%
Percentile
43.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS
8.7 · NONE
CVSS v4.0
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
EPSS
0.00524 · 43.6th percentile
Weakness
CWE-190 · Integer Overflow or Wraparound
Published
2026-08-20T22:16Z
References (6)
EPSS history
Timeline
  • 20 AUG 17:53Z
    Libevent: `evtag_unmarshal_header()` decodes a wire `uint32` length into a signed `int` return value.
    cvelistv5