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
Published
2026-08-20T17:50:09Z
Modified
2026-09-11T08:36:41Z
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 
{
    "extracted_events": [
        {
            "introduced": "2.2.0-alpha"
        },
        {
            "fixed": "2.2.2-alpha"
        },
        {
            "introduced": "0"
        },
        {
            "fixed": "2.1.13"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

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 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63381.json"
vanir_signatures 
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vanir_signatures_modified 
"2026-09-11T08:36:41Z"