CVE-2026-27459

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Source
https://cve.org/CVERecord?id=CVE-2026-27459
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-27459.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-27459
Aliases
Downstream
Related
Published
2026-03-17T23:34:28.483Z
Modified
2026-03-19T12:52:08.762514Z
Severity
  • 7.2 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U CVSS Calculator
Summary
pyOpenSSL DTLS cookie callback buffer overflow
Details

pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0, if a user provided callback to set_cookie_generate_callback returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values that are too long are now rejected.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-120"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27459.json"
}
References

Affected packages

Git / github.com/pyca/pyopenssl

Affected ranges

Type
GIT
Repo
https://github.com/pyca/pyopenssl
Events
Introduced
819095fa886db98cf43b6f0e66ba19c83d64d3c0
Fixed
358cbf29c4e364c59930e53a270116249581eaa3

Affected versions

22.*
22.0.0
22.1.0
23.*
23.0.0
23.1.0
23.2.0
23.3.0
24.*
24.0.0
24.1.0
24.2.0
24.2.1
24.3.0
25.*
25.0.0
25.1.0
25.2.0
25.3.0

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-27459.json"