USN-8557-1

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Source
https://ubuntu.com/security/notices/USN-8557-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8557-1.json
JSON Data
https://api.osv.dev/v1/vulns/USN-8557-1
Upstream
Related
Published
2026-07-16T17:44:41Z
Modified
2026-07-17T01:35:30.249393198Z
Summary
python-authlib vulnerabilities
Details

Jay Neiva and Mauro Carrillo discovered that Authlib did not properly validate cryptographic keys embedded in JWT headers. An attacker could possibly use this issue to forge trusted tokens, resulting in authentication and authorization bypass. (CVE-2026-27962)

Jay Neiva and Mauro Carrillo discovered that Authlib incorrectly handled RSA1_5 encrypted tokens. An attacker could possibly use this issue to recover sensitive encrypted information, resulting in information disclosure. (CVE-2026-28490)

Jay Neiva and Mauro Carrillo discovered that Authlib did not properly reject unsupported cryptographic algorithms when validating OpenID Connect ID tokens. An attacker could possibly use this issue to bypass token integrity checks, resulting in authentication bypass. (CVE-2026-28498)

Johnny Deuss discovered that Authlib did not provide cross-site request forgery protection for the OAuth cache feature in its Starlette integration. An attacker could possibly use this issue to perform unauthorized OAuth actions, resulting in cross-site request forgery. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04 LTS. (CVE-2026-41425)

References

Affected packages

Ubuntu:Pro:22.04:LTS / python-authlib

Package

Name
python-authlib
Purl
pkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps%2Fjammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
0.15.5-1ubuntu0.1~esm2

Affected versions

0.*
0.15.4-1
0.15.5-1
0.15.5-1ubuntu0.1~esm1

Ecosystem specific 

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_version": "0.15.5-1ubuntu0.1~esm2",
            "binary_name": "python3-authlib"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8557-1.json"
cves_map 
{
    "cves": [
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-27962"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-28490"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-28498"
        }
    ],
    "ecosystem": "Ubuntu:Pro:22.04:LTS"
}

Ubuntu:Pro:24.04:LTS / python-authlib

Package

Name
python-authlib
Purl
pkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps%2Fnoble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.3.0-1ubuntu0.1~esm2

Affected versions

1.*
1.2.1-1
1.3.0-1
1.3.0-1ubuntu0.1~esm1

Ecosystem specific 

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_version": "1.3.0-1ubuntu0.1~esm2",
            "binary_name": "python3-authlib"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8557-1.json"
cves_map 
{
    "cves": [
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-27962"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-28490"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-28498"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-41425"
        }
    ],
    "ecosystem": "Ubuntu:Pro:24.04:LTS"
}

Ubuntu:Pro:26.04:LTS / python-authlib

Package

Name
python-authlib
Purl
pkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps%2Fresolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.6.7-1ubuntu0.1~esm1

Affected versions

1.*
1.6.0-1
1.6.5-1
1.6.6-1
1.6.7-1

Ecosystem specific 

{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_version": "1.6.7-1ubuntu0.1~esm1",
            "binary_name": "python3-authlib"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8557-1.json"
cves_map 
{
    "cves": [
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-27962"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-28490"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V4",
                    "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
                },
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-28498"
        },
        {
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ],
            "id": "CVE-2026-41425"
        }
    ],
    "ecosystem": "Ubuntu:Pro:26.04:LTS"
}