{"attribution":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","cve":{"id":"CVE-2026-59884","sourceIdentifier":"security-advisories@github.com","published":"2026-07-14T17:17:14.750","lastModified":"2026-07-21T14:37:52.160","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER decoder shared by the CER and DER codecs parses long-form tags by accumulating continuation octets without an upper bound on the tag ID size, allowing a crafted input to force construction of an arbitrarily large integer with CPU cost growing quadratically and to trigger unhandled ValueError exceptions in Python 3.11+ error formatting paths. Any application decoding untrusted BER, CER, or DER input is affected. This issue is fixed in version 0.6.4."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"pyasn1","product":"pyasn1","versions":[{"version":"\u003c 0.6.4","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-15T13:50:17.314569Z","id":"CVE-2026-59884","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-400"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:pyasn1:pyasn1:*:*:*:*:*:python:*:*","versionEndExcluding":"0.6.4","matchCriteriaId":"9AFAC251-9C55-4538-A9B2-28C2923FBB01"}]}]}],"references":[{"url":"https://github.com/pyasn1/pyasn1/commit/628e36ecbb5277a3f01572ce418ef54271b165a5","source":"security-advisories@github.com","tags":["Patch"]},{"url":"https://github.com/pyasn1/pyasn1/releases/tag/v0.6.4","source":"security-advisories@github.com","tags":["Release Notes"]},{"url":"https://github.com/pyasn1/pyasn1/security/advisories/GHSA-m4p7-r5rc-7g4j","source":"security-advisories@github.com","tags":["Third Party Advisory"]}]}}