CVE-2026-63384 (GCVE-0-2026-63384)

Vulnerability from cvelistv5 – Published: 2026-08-20 17:53 – Updated: 2026-08-20 19:50
VLAI
Title
Libevent: `evtag_unmarshal_header()` decodes a wire `uint32` length into a signed `int` return value.
Summary
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.
Severity
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
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 19:50 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
References
Impacted products
Vendor Product Version
libevent libevent Affected: >= 2.2.0-alpha, < 2.2.2-alpha
Affected: < 2.1.13
Create a notification for this product.
Show details on NVD website
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