Description
OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. Prior to 4.0.0, the client_credentials and Resource Owner Password Credentials token grant handlers can authenticate request.client as one confidential client while retaining an attacker-supplied request.client_id for validate_grant_type and validate_scopes. A lower-privilege authenticated client can therefore cause grant and scope authorization to use another client's identity when an application validator relies on the documented client_id argument, potentially issuing tokens with unauthorized grants or scopes. Validators that authorize exclusively from request.client may not be affected. This issue is fixed in version 4.0.0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| oauthlib | oauthlib | < 4.0.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | python-oauthlib | No fix yet | — |
| Debian 13 | python-oauthlib | No fix yet | — |
| Debian 12 | python-oauthlib | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | python-oauthlib | No fix yet | — |
| Ubuntu 26.04 LTS | python-oauthlib | No fix yet | — |
| Ubuntu 24.04 LTS | python-oauthlib | No fix yet | — |
| Ubuntu 22.04 LTS | python-oauthlib | No fix yet | — |
| Ubuntu 20.04 LTS | python-oauthlib | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | python-oauthlib | No fix yet | — |
| Ubuntu 16.04 LTS | python-oauthlib | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | python-oauthlib +1 | 3.2.2-6.el10_3.1 | RHSA-2026:98641 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.8 EUS | python-oauthlib +1 | 3.1.1-5.el9_8.1 | RHSA-2026:99167 |
| RHEL 8.6 EUS Long Life | python-oauthlib +1 | 2.1.0-1.el8_6.1 | RHSA-2026:98118 |
| RHEL 8.6 AUS | python-oauthlib +1 | 2.1.0-1.el8_6.1 | RHSA-2026:98118 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | python3-oauthlib | 3.2.2-6.el10_3.1 | RLSA-2026:98641 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python-oauthlib | 4.0.1-1.1 | openSUSE-SU-2026:12520-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | python-oauthlib | No fix yet | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
-
federiconbaez/cortex9-oauthlib-token-grant-client-id-confusion-model ★ 0 · Nov 9, 2026
Offline educational model of CVE-2026-118669 (OAuthLib token-grant client_id confusion)
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | oauthlib | < 4.0.0 | 4.0.0 | GHSA-7984-qgvg-3j9c |
Advisories 6
- RHSA-2026:99167 Red Hat Security Advisory: python-oauthlib security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:98641 Red Hat Security Advisory: python-oauthlib security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:98118 Red Hat Security Advisory: python-oauthlib security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RLSA-2026:98641 Important: python-oauthlib security update Rocky Linux Security Advisories · Nov 13, 2026
- WID-SEC-2026-4472 Red Hat Enterprise Linux (python-jwcrypto, sos, hickory-resolver, libimobiledevice, gcc, python-oauthlib): Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- openSUSE-SU-2026:12520-1 python313-oauthlib-4.0.1-1.1 on GA media SUSE / openSUSE Security Updates · Nov 11, 2026