ansible@9 · OAuthLib: Token grants can use attacker-supplied client_id for authorization after authenticating a different client
Affects ansible@9Source GCVE Database
Not known to be exploited · CVSS 8.4 High.
Data as of 31 Oct 2026, 17:21 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 8.4 |
|---|
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewansible@9pkg:brew/ansible%409Other threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
As a mitigation, applications should ensure their RequestValidator implementations do not rely solely on the client_id argument passed by OAuthlib for authorization, but instead authorize based on the authenticated client object (request.client). Validators ignoring the client_id argument and authorizing only from request.client may not be affected.
Description
OAuthlib's token grant handlers allow an authenticated low-privilege client to supply a different client_id in the token request body, causing authorization checks to be performed under that other client identity. This affects the client_credentials and password grant flows where the application validator uses the client_id argument for authorization. The flaw enables a token authorization bypass where a low-privilege client can obtain tokens with scopes or grant types assigned to a higher-privilege client.
References
- github.com/oauthlib/oauthlib/security/advisories/GHSA-7984-qgvg-3j9c (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-118669 (opens in a new tab)
- github.com/oauthlib/oauthlib/pull/920 (opens in a new tab)
- github.com/oauthlib/oauthlib/commit/c951a1d09f99f14e3240973fa83c4f4287d4753d (opens in a new tab)
- github.com/oauthlib/oauthlib (opens in a new tab)
- github.com/oauthlib/oauthlib/releases/tag/v4.0.0 (opens in a new tab)