{"items":[{"id":"NVI-00012951","kind":"vulnerability","title":"PyJWT: Unauthenticated RecursionError DoS in pre-verification payload parse (PyJWKClient.get_signing_key_from_jwt / verify_signature=False)","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-42vr-xj54-vc7v","CVE-2026-101918"],"plain_summary":"GitHub lists this reviewed advisory for PyJWT. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-1af50affe000fb667db46167de4e6d3e"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-30T15:41:07.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-1b87ee90d9fa2dacd83fe269a3b17c12"},{"kind":"EPSS","as_of":"2026-11-02T12:00:30.000Z","value":"0.413%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.35583. Missing scores are unknown.","source_id":"sr-1af50affe000fb667db46167de4e6d3e"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-1b87ee90d9fa2dacd83fe269a3b17c12","url":"https://github.com/advisories/GHSA-42vr-xj54-vc7v","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-42vr-xj54-vc7v","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:22:52.960Z"},{"id":"sr-1af50affe000fb667db46167de4e6d3e","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-101918","publisher":"FIRST EPSS","observed_at":"2026-11-02T20:15:58.837Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-1b87ee90d9fa2dacd83fe269a3b17c12"],"technology":"PyJWT","known_exclusions":[],"conditions_summary":"## Summary\n\n`PyJWKClient.get_signing_key_from_jwt(token)` — the first step of the JWKS\nverification flow documented in `docs/usage.rst` — must decode a token's\npayload before its signature can be checked, via\n`jwt.api_jwt.decode_complete(token, options={\"verify_signature\": False})`.\nThat call parses the payload with `json.loads` in `PyJWT._decode_payload`\n(`jwt/api_jwt.py:297-300`), whose `except` clause catches only `ValueError`.\nA payload that is valid JSON but nested ~20,000 levels deep makes\n`json.loads` raise `RecursionError`, which is **not** a `ValueError` and\nescapes as a raw, undocumented exception type — not `DecodeError`,\n`InvalidTokenError`, or `PyJWTError`, so every documented error-handling\npattern in `docs/usage.rst` misses it.\n\nThe token needs no valid signature and no network access — the crash\nhappens during payload parsing, before the `kid` is even looked up. A\nsingle unauthenticated ~50KB request crashes the caller's auth handler\n(HTTP 500 / dead worker), repeatably. The same path is reachable through\nplain `jwt.decode(token, options={\"verify_signature\": False})` too.\n\nNotably, this project already fixed the **identical** bug class for the\nJWS **header** path — ","public_affected_ranges":[">= 2.0.0a1, <= 2.14.0"]}],"null_published_at":"2026-11-07T14:01:55.437Z","source_updated_at":"2026-09-30T15:41:07.000Z","source_disclosed_at":"2026-09-30T15:41:05.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-01T07:22:52.960Z"},{"id":"NVI-00012951","kind":"vulnerability","title":"PyJWT: Unauthenticated RecursionError DoS in pre-verification payload parse (PyJWKClient.get_signing_key_from_jwt / verify_signature=False)","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-42vr-xj54-vc7v","CVE-2026-101918"],"plain_summary":"GitHub lists this reviewed advisory for PyJWT. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-1b87ee90d9fa2dacd83fe269a3b17c12"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-30T15:41:07.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-1b87ee90d9fa2dacd83fe269a3b17c12"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-1b87ee90d9fa2dacd83fe269a3b17c12","url":"https://github.com/advisories/GHSA-42vr-xj54-vc7v","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-42vr-xj54-vc7v","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:22:52.960Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-1b87ee90d9fa2dacd83fe269a3b17c12"],"technology":"PyJWT","known_exclusions":[],"conditions_summary":"## Summary\n\n`PyJWKClient.get_signing_key_from_jwt(token)` — the first step of the JWKS\nverification flow documented in `docs/usage.rst` — must decode a token's\npayload before its signature can be checked, via\n`jwt.api_jwt.decode_complete(token, options={\"verify_signature\": False})`.\nThat call parses the payload with `json.loads` in `PyJWT._decode_payload`\n(`jwt/api_jwt.py:297-300`), whose `except` clause catches only `ValueError`.\nA payload that is valid JSON but nested ~20,000 levels deep makes\n`json.loads` raise `RecursionError`, which is **not** a `ValueError` and\nescapes as a raw, undocumented exception type — not `DecodeError`,\n`InvalidTokenError`, or `PyJWTError`, so every documented error-handling\npattern in `docs/usage.rst` misses it.\n\nThe token needs no valid signature and no network access — the crash\nhappens during payload parsing, before the `kid` is even looked up. A\nsingle unauthenticated ~50KB request crashes the caller's auth handler\n(HTTP 500 / dead worker), repeatably. The same path is reachable through\nplain `jwt.decode(token, options={\"verify_signature\": False})` too.\n\nNotably, this project already fixed the **identical** bug class for the\nJWS **header** path — ","public_affected_ranges":[">= 2.0.0a1, <= 2.14.0"]}],"null_published_at":"2026-11-01T07:29:12.904Z","source_updated_at":"2026-09-30T15:41:07.000Z","source_disclosed_at":"2026-09-30T15:41:05.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-01T07:22:52.960Z"}],"next_cursor":null,"snapshot_revision":"42594"}