CVE-2026-63381
Description
A flaw was found in Libevent, an event notification library. A use-after-free vulnerability exists in the evbuffer_add_buffer_reference function when it processes an output buffer with a zero length. This can lead to a dangling pointer, which an attacker could exploit to cause memory corruption or crash the application.
Statement
Red Hat Enterprise Linux, OpenShift (RHCOS), RHIVOS, and community products (Fedora, Hummingbird) ship affected versions of libevent.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.6 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | Low | N/A | N/A |
| Integrity Impact | Low | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
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