CVE-2026-63381

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Source
https://cve.org/CVERecord?id=CVE-2026-63381
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63381.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-63381
Aliases
  • GHSA-c2pj-cg4r-88c8
Downstream
ALSA (2)
AZL (4)
BELL (1)
CLSA (1)
DEBIAN (1)
ECHO (1)
MGASA (1)
OESA (1)
openSUSE (1)
RHSA (3)
RLSA (2)
ROOT (1)
UBUNTU (1)
Related
ALSA (2)
openSUSE (1)
Published
2026-08-20T17:50:09Z
Modified
2026-10-29T12:27:01Z
Severity
  • 5.8 (Medium) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
Libevent: Dangling Pointer in `evbuffer_add_buffer_reference`
Details

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free in buffer.c when evbuffer_add_buffer_reference processes an output buffer whose out_total_len is zero. evbuffer_free_all_chains frees the initial empty chain without resetting outbuf->first, outbuf->last, or outbuf->last_with_datap, and APPEND_CHAIN_MULTICAST subsequently dereferences the dangling chain pointer. A caller that can drive this buffer state can cause memory corruption or a process crash. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

Database specific 
{
    "cna_assigner":  "GitHub_M",
    "cwe_ids":  [
        "CWE-908"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63381.json"
}
References

Affected packages

Git / github.com/libevent/libevent

Affected ranges

Type
GIT
Repo
https://github.com/libevent/libevent
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
df3ecad3a040fd6d4fad4287defe113395de6fd7
Fixed
79ddfb460847999b807cba76d04e73891f29c6ee
Fixed
5cb95ba2f804f8aff46f88d58391c71e1251cd1c
Fixed
9db091b04f569be3a700fa9860ef02f90b830af9
Database specific
Show details 
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            "strategy":  "StringRangeExpression"
        },
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}

Affected versions

release-1.*
release-1.1b
release-2.*
release-2.0.1-alpha
release-2.0.10-stable
release-2.0.3-alpha
release-2.0.4-alpha
release-2.0.5-beta
release-2.0.6-rc
release-2.0.7-rc
release-2.0.8-rc
release-2.0.9-rc
release-2.1.1-alpha
release-2.1.10-stable
release-2.1.11-stable
release-2.1.12-stable
release-2.1.2-alpha
release-2.1.3-alpha
release-2.1.4-alpha
release-2.1.5-beta
release-2.1.6-beta
release-2.1.7-rc
release-2.1.8-stable
release-2.1.9-beta
release-2.2.1-alpha

Database specific

source 
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vanir_signatures_modified 
"2026-10-28T11:16:59Z"