BREW-CRYPTOGRAPHY-CVE-20… (CVE-2026-69249)
Vulnerability from osv_homebrew – Published: 2026-08-13 16:41 – Updated: 2026-10-08 00:03 – Source websitepython-cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. In versions 42.0.0 through 48.0.0, when resolving invalid certificate chains that include duplicate copies of self-signed certificates, the processing recursively invokes the same candidate, leading to an exponential blowup. Although the limitation that the chain depth cannot exceed a specified maximum depth prevents unbounded recursion and guarantees termination, an attacker-controlled certificate chain can lead the processing to easily take more than 5s to reject in testing. This amplification could form the basis for a resource exhaustion denial of service attack. The core issue arises in the recursive nature of build_chain_inner, which does not de-duplicate against previously analyzed candidates. As the correctness of validation is not affected, the integrity of a system cannot be compromised through this vector, only its availability. This issue is fixed in 49.0.0.
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"upstream_fixed_in": "49.0.0"
},
"package": {
"ecosystem": "Homebrew",
"name": "cryptography",
"purl": "pkg:brew/cryptography"
},
"ranges": [
{
"events": [
{
"introduced": "42.0.5"
},
{
"fixed": "49.0.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "git",
"upstream_evidence": [
{
"ecosystem": "GIT",
"key": "https://github.com/pyca/cryptography",
"name": "https://github.com/pyca/cryptography",
"strategy": "git",
"subject_version": "50.0.2"
},
{
"ecosystem": "PyPI",
"key": "pkg:pypi/cryptography@50.0.2",
"name": "cryptography",
"strategy": "registry",
"subject_version": "50.0.2"
}
]
},
"details": "python-cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. In versions 42.0.0 through 48.0.0, when resolving invalid certificate chains that include duplicate copies of self-signed certificates, the processing recursively invokes the same candidate, leading to an exponential blowup. Although the limitation that the chain depth cannot exceed a specified maximum depth prevents unbounded recursion and guarantees termination, an attacker-controlled certificate chain can lead the processing to easily take more than 5s to reject in testing. This amplification could form the basis for a resource exhaustion denial of service attack. The core issue arises in the recursive nature of build_chain_inner, which does not de-duplicate against previously analyzed candidates. As the correctness of validation is not affected, the integrity of a system cannot be compromised through this vector, only its availability. This issue is fixed in 49.0.0.",
"id": "BREW-cryptography-CVE-2026-69249",
"modified": "2026-10-08T00:03:43Z",
"published": "2026-08-13T16:41:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69249.json"
},
{
"type": "ADVISORY",
"url": "https://github.com/pyca/cryptography/security/advisories/GHSA-jwv3-5hgf-82ww"
},
{
"type": "ADVISORY",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/cryptography/PYSEC-2026-3553.yaml"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-69249"
},
{
"type": "FIX",
"url": "https://github.com/pyca/cryptography/commit/3763aa79b"
},
{
"type": "FIX",
"url": "https://github.com/pyca/cryptography/commit/4a12cf49675a184e47f912b00b04f3a629283582"
},
{
"type": "FIX",
"url": "https://github.com/pyca/cryptography/pull/14960"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "python-cryptography: Duplicate self-signed intermediates can cause exponential path-building",
"upstream": [
"CVE-2026-69249",
"GHSA-jwv3-5hgf-82ww",
"PYSEC-2026-3553"
]
}
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