{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-48525", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-21T16:18:10.619Z", "datePublished": "2026-05-28T15:11:12.483Z", "dateUpdated": "2026-06-23T15:54:09.003Z" }, "containers": { "cna": { "title": "PyJWT: Unauthenticated DoS via unbounded Base64URL decoding of unused payload segment in b64=false detached JWS", "problemTypes": [ { "descriptions": [ { "cweId": "CWE-400", "lang": "en", "description": "CWE-400: Uncontrolled Resource Consumption", "type": "CWE" } ] } ], "metrics": [ { "cvssV3_1": { "attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "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:L", "version": "3.1" } } ], "references": [ { "name": "https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w7vc-732c-9m39", "tags": [ "x_refsource_CONFIRM" ], "url": "https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w7vc-732c-9m39" } ], "affected": [ { "vendor": "jpadilla", "product": "pyjwt", "versions": [ { "version": ">= 2.8.0, < 2.13.0", "status": "affected" } ] } ], "providerMetadata": { "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-05-28T15:11:12.483Z" }, "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 “work amplifier”: 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." } ], "source": { "advisory": "GHSA-w7vc-732c-9m39", "discovery": "UNKNOWN" } }, "adp": [ { "references": [ { "url": "https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w7vc-732c-9m39", "tags": [ "exploit" ] } ], "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-05-28T15:58:48.873096Z", "id": "CVE-2026-48525", "options": [ { "Exploitation": "poc" }, { "Automatable": "yes" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-23T15:54:09.003Z" } } ] } }