DEBIAN-CVE-2026-28498

Source
https://security-tracker.debian.org/tracker/CVE-2026-28498
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-28498.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-28498
Upstream
Published
2026-03-16T18:16:07Z
Modified
2026-09-11T08:47:37Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
Summary
[none]
Details

Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to version 1.6.9, a library-level vulnerability was identified in the Authlib Python library concerning the validation of OpenID Connect (OIDC) ID Tokens. Specifically, the internal hash verification logic (_verify_hash) responsible for validating the at_hash (Access Token Hash) and c_hash (Authorization Code Hash) claims exhibits a fail-open behavior when encountering an unsupported or unknown cryptographic algorithm. This flaw allows an attacker to bypass mandatory integrity protections by supplying a forged ID Token with a deliberately unrecognized alg header parameter. The library intercepts the unsupported state and silently returns True (validation passed), inherently violating fundamental cryptographic design principles and direct OIDC specifications. This issue has been patched in version 1.6.9.

References

Affected packages

Debian:12 / python-authlib

Package

Name
python-authlib
Purl
pkg:deb/debian/python-authlib?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.2.0-1+deb12u2

Affected versions

1.*
1.2.0-1
1.2.0-1+deb12u1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-28498.json"

Debian:13 / python-authlib

Package

Name
python-authlib
Purl
pkg:deb/debian/python-authlib?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.6.0-1
1.6.0-1+deb13u1
1.6.1-1
1.6.3-1
1.6.4-1
1.6.5-1
1.6.6-1
1.6.7-1
1.6.8-1
1.6.9-1
1.7.0-1
1.7.2-1
1.7.2-2

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-28498.json"

Debian:14 / python-authlib

Package

Name
python-authlib
Purl
pkg:deb/debian/python-authlib?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.6.9-1

Affected versions

1.*
1.6.0-1
1.6.1-1
1.6.3-1
1.6.4-1
1.6.5-1
1.6.6-1
1.6.7-1
1.6.8-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-28498.json"