---
id: CVE-2026-63384
title: Libevent is an event notification library
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…
severity: high
cwe:
  - CWE-190
published: '2026-08-20'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T21:19:49.197'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-63384'
references:
  - url: >-
      https://github.com/libevent/libevent/commit/109c16499282959d70f56ec3baf4c8b1e6646bda
    label: security-advisories@github.com
  - url: >-
      https://github.com/libevent/libevent/commit/5e3c6ebe342b34c5a9bcf48e9a32ad6708b9c416
    label: security-advisories@github.com
  - url: 'https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable'
    label: security-advisories@github.com
  - url: 'https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha'
    label: security-advisories@github.com
  - url: >-
      https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8
    label: security-advisories@github.com
  - url: >-
      https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63384.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-63384'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2520658'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-63384'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-63384'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60853'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67909'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67908'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67910'
  - url: 'https://access.redhat.com/errata/RHSA-2026:71603'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00524
epssPercentile: 0.41992
ingestedAt: '2026-09-09T21:22:45.545Z'
vendor: Red Hat
product: Red Hat Enterprise Linux 6
affected:
  - enterprise_linux 10
  - enterprise_linux 6
  - enterprise_linux 7
  - enterprise_linux 8
  - enterprise_linux 9
  - openshift_container_platform 4
  - hardened_images
patched:
  - hardened_images
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:60853** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-29 · [advisory](https://access.redhat.com/errata/RHSA-2026:60853)
- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat OpenShift Container Platform 4 · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63384.json)
- **RHSA-2026:67909** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:67909)
- **RHSA-2026:67908** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux BaseOS (v. 8) · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:67908)
- **RHSA-2026:67910** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9) · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:67910)
- **RHSA-2026:71603** · Red Hat · fixed in: Red Hat Update Infrastructure 5 · released 2026-09-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:71603)