Python authlib: From version 1.6.5 to before version 1.6.7, previous tests involving passing a malicious JWT
Affects python-authlibSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 1.6.7 : patch python-authlib as a priority.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.6.7
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 6 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10python-authlibpkg:deb/ubuntu/python-authlib?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
Authlib is a Python library which builds OAuth and OpenID Connect servers. From version 1.6.5 to before version 1.6.7, previous tests involving passing a malicious JWT containing alg: none and an empty signature was passing the signature verification step without any changes to the application code when a failure was expected.. This issue has been patched in version 1.6.7.
References
- ubuntu.com/security/CVE-2026-28802 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-28802 (opens in a new tab)
- github.com/authlib/authlib/commit/a61c2acb807496e67f32051b5f1b1d5ccf8f0a75 (opens in a new tab)
- github.com/authlib/authlib/commit/b87c32ed07b8ae7f805873e1c9cafd1016761df7 (opens in a new tab)
- github.com/authlib/authlib/security/advisories/GHSA-7wc2-qxgw-g8gg (opens in a new tab)