CVE-2026-48525

{"id": "CVE-2026-48525", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 3.9}]}, "published": "2026-05-28T16:16:29.533", "references": [{"url": "https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w7vc-732c-9m39", "tags": ["Exploit", "Vendor Advisory", "Mitigation"], "source": "security-advisories@github.com"}, {"url": "https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w7vc-732c-9m39", "tags": ["Exploit", "Vendor Advisory", "Mitigation"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-400"}]}], "descriptions": [{"lang": "en", "value": "PyJWT is a JSON Web Token implementation in Python. From 2.8.0 to 2.12.1, when verifying detached JWS tokens using the unencoded-payload option (\"b64\": false, RFC 7797), PyJWT performs Base64URL decoding of the compact-serialization payload segment before enforcing the detached-payload rules. For b64=false, PyJWT later discards that decoded payload and replaces it with the caller-provided detached_payload. In practice, this turns the middle segment into an attacker-controlled \u201cwork amplifier\u201d: a remote client can supply an arbitrarily large Base64URL payload segment that forces CPU work + memory allocations even if the signature is invalid. This creates an unauthenticated DoS vector against any endpoint that verifies detached JWS using PyJWT. This vulnerability is fixed in 2.13.0."}], "lastModified": "2026-06-01T17:45:15.763", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "71DC0C43-352F-449C-B411-5040A311A35F", "versionEndIncluding": "2.12.1", "versionStartIncluding": "2.8.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}