{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-119196","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-10-29T16:04:48.728Z","datePublished":"2026-10-29T19:44:46.031Z","dateUpdated":"2026-10-29T19:44:46.031Z"},"containers":{"cna":{"title":"pyasn1: Quadratic CPU consumption in constructed BIT STRING decoding","problemTypes":[{"descriptions":[{"cweId":"CWE-407","lang":"en","description":"CWE-407: Inefficient Algorithmic Complexity","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-2qm8-x737-gmw5","tags":["x_refsource_CONFIRM"],"url":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-2qm8-x737-gmw5"},{"name":"https://github.com/pyasn1/pyasn1/pull/132","tags":["x_refsource_MISC"],"url":"https://github.com/pyasn1/pyasn1/pull/132"},{"name":"https://github.com/pyasn1/pyasn1/commit/73ba7b043cc7e92cb37f16f2c955bff93b0e6f6c","tags":["x_refsource_MISC"],"url":"https://github.com/pyasn1/pyasn1/commit/73ba7b043cc7e92cb37f16f2c955bff93b0e6f6c"},{"name":"https://github.com/pyasn1/pyasn1/releases/tag/v0.6.5","tags":["x_refsource_MISC"],"url":"https://github.com/pyasn1/pyasn1/releases/tag/v0.6.5"}],"affected":[{"vendor":"pyasn1","product":"pyasn1","versions":[{"version":"< 0.6.5","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-10-29T19:44:46.031Z"},"descriptions":[{"lang":"en","value":"pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, constructed BIT STRING decoding repeatedly shifts and copies the complete bit value accumulated from earlier fragments. Attacker-controlled BER or CER input contains many constructed BIT STRING fragments; schema-driven DER also accepts a definite-length constructed BIT STRING. BitStringPayloadDecoder repeatedly calls BitString.fromOctetString with the prior bitString as prepend, shifting an ever-growing SizedInteger for each fragment and causing quadratic work. Large fragmented values can exhaust CPU during decode() without requiring later conversion or formatting. This issue is fixed in version 0.6.5."}],"source":{"advisory":"GHSA-2qm8-x737-gmw5","discovery":"UNKNOWN"}}}}