CVE-2026-49272: oauthlib · Improper Authentication
Affects oauthlibSource CVE Database V5
Public exploit available · CVSS 8.5 High : upgrade to 4.0.1 as a priority.
Data as of 5 Nov 2026, 21:19 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 8.5 |
|---|
- CISA SSVC
- Exploitation
- Proof of concept is public or traded
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-05.
- Patch
- Available – fixed in 4.0.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 5 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CISA SSVC: proof of concept public
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
Timeline
CVE ID reserved
by GitHub, Inc.
, 161 days before disclosure
CVE published
on cve.org
, t = 0
CISA SSVC assessment
proof of concept public
, 16 minutes after disclosure
In Threat Radar
record ingested
, 21 minutes after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA SSVC, the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade oauthlib to 4.0.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| oauthliboauthlib | Affected
| Fixed in
|
AI-suggested
Upgrade OAuthLib to version 4.0.1 or later, where the vulnerability is fixed. No other mitigations are indicated by the vendor advisory.
Description
OAuthLib versions from 3.3.0 up to but not including 4.0.1 contain an improper authentication vulnerability in the RFC 8628 device workflow. The DeviceCodeGrant.validate_token_request method does not verify the presence or validity of the device_code parameter. This allows an attacker who knows a valid client ID enabled for the device workflow to submit a missing or invalid device code and obtain a bearer token without completing device authorization. The issue is resolved in version 4.0.1.
References
- github.com/oauthlib/oauthlib/security/advisories/GHSA-3jp2-3mrg-2vxc (opens in a new tab)
- github.com/oauthlib/oauthlib/pull/954 (opens in a new tab)
- github.com/oauthlib/oauthlib/commit/77a5f1c8ce00da2b0b8c5f6e9cc129920085f114 (opens in a new tab)
- github.com/oauthlib/oauthlib/releases/tag/v4.0.1 (opens in a new tab)