ETK-2026-3648Zero's internal tracking ID, independent of the CVE number.
waiting for further signalsZero needs more public information before it can validate it.description
Authlib applications using authlib.jose are affected when they supply certain OpenSSH public-key material to JWT verification without limiting allowed algorithms. An attacker who has the public key may create an HMAC-signed token that the application accepts, including attacker-chosen claims.
mitigation
Upgrade authlib to 1.9.5. Until upgraded, explicitly allow only the expected asymmetric algorithms and pass typed key objects rather than raw key bytes.
fixed in 1.9.5
outcome
Contextual, not validated: no deterministic check could cover this one, and no technique passed our review.
source signals
Public signals that triggered or updated the pipeline. These are inputs for the deltas above.
- 2026-11-05 16:18Zghsa: trigger signal, started the run
this entry in the feed
GET /api/v1/feed/ETK-2026-3648
{ "etk_id": "ETK-2026-3648", "cve_id": null, "display_id": "ETK-2026-3648", "ghsa_id": "GHSA-f7j6-p4qx-gq99", "euvd_id": null, "status": "published", "anchor_state": "awaiting_cve", "title": "JWT algorithm confusion in authlib.jose key handling", "summary": "Authlib applications using authlib.jose are affected when they supply certain OpenSSH public-key material to JWT verification without limiting allowed algorithms. An attacker who has the public key may create an HMAC-signed token that the application accepts, including attacker-chosen claims.", "mitigation": "Upgrade authlib to 1.9.5. Until upgraded, explicitly allow only the expected asymmetric algorithms and pass typed key objects rather than raw key bytes.", "vendor": "pip", "product": "pip:Authlib", "affected": [ { "affected_notes": [], "affected_ranges": [ ">= 1.3.1, <= 1.9.4" ], "ecosystem": "pip", "fixed_versions": [ "1.9.5" ], "package_name": "authlib", "purl": "pkg:pypi/authlib" } ], "cwes": [ 184 ], "cvss_score": 7.4, "cvss_src": "cna_vendor", "cvss_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N", "epss_score": null, "epss_percentile": null, "epss_asof": null, "automation": "contextual", "check": false, "check_confidence_basis": null, "exploit": false, "pipeline_minutes": 9.766850033333334, "t0_at": null, "signals": { "trigger_signal": { "at": "2026-11-05T16:18:09+00:00", "days": -0.048113632094907405, "is_lower_bound": true, "measured_at": "2026-11-05T17:27:26.077174+00:00", "url": "https://github.com/authlib/authlib/security/advisories/GHSA-f7j6-p4qx-gq99" } } }
published 2026-11-05 16:47Z
last change 2026-11-05 17:15Z
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