Upstream information
Description
Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.0, OpenIDMixin.parse_id_token() reads the nonce_supported decision from the untrusted ID token being validated and sets the expected nonce to null when that claim is the JSON boolean false. In implicit and hybrid relying parties, or applications that directly accept externally supplied ID tokens, an attacker with a captured validly signed token can bypass the nonce-to-session binding and replay the victim's token into an attacker-controlled session. Plain authorization code flow is not affected, and the token must still pass signature, issuer, and audience validation. OpenIDMixin.parse_id_token() trusts nonce_supported in both authlib/integrations/base_client/sync_openid.py and authlib/integrations/base_client/async_openid.py to disable the expected nonce. This issue is fixed in version 1.9.0.SUSE information
Overall state of this security issue: Pending
This issue is currently rated as having moderate severity.
| CVSS detail | CNA (GitHub) | SUSE |
|---|---|---|
| Base Score | 4.2 | 4.2 |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N |
| Attack Vector | Network | Network |
| Attack Complexity | High | High |
| Privileges Required | None | None |
| User Interaction | Required | Required |
| Scope | Unchanged | Unchanged |
| Confidentiality Impact | Low | Low |
| Integrity Impact | Low | Low |
| Availability Impact | None | None |
| CVSSv3 Version | 3.1 | 3.1 |
| CVSS detail | SUSE |
|---|---|
| Base Score | 2.3 |
| Vector | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N |
| Attack Vector | Network |
| Attack Complexity | High |
| Attack Requirements | None |
| Privileges Required | None |
| User Interaction | Passive |
| Vulnerable System Confidentiality Impact | Low |
| Vulnerable System Integrity Impact | Low |
| Vulnerable System Availability Impact | None |
| Subsequent System Confidentiality Impact | None |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| SUSE Linux Enterprise Desktop 15 SP7 | python-Authlib | Affected |
| SUSE Linux Enterprise Module for Python 3 15 SP7 | python-Authlib | Affected |
| SUSE Linux Enterprise Server 15 SP7 | python-Authlib | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | python-Authlib | Affected |
| Products under Long Term Service Pack support and receiving important and critical security fixes. | ||
| SUSE Linux Enterprise Module for Python 3 15 SP6 | python-Authlib | Affected |
| SUSE Linux Enterprise Server 15 SP6 | python-Authlib | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | python-Authlib | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | python-Authlib | Affected |
| Products past their end of life and not receiving proactive updates anymore. | ||
| SUSE Linux Enterprise Desktop 15 SP6 | python-Authlib | Affected |
| openSUSE Leap 15.6 | python-Authlib | Affected |
SUSE Timeline for this CVE
CVE page created: Fri Oct 23 21:55:02 2026CVE page last modified: Fri Oct 23 21:55:02 2026