CVE-2026-49272
OAuthLib: Bearer token can be retrieved as long as client knows a valid client ID for device workflow
Description
OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 3.3.0 until 4.0.1, OAuthLib's RFC 8628 device workflow does not require DeviceCodeGrant.validate_token_request to check that the device_code parameter is present and valid. A caller whose client request is accepted by the configured validator and who knows a valid client ID enabled for the device workflow can submit a missing or bogus device code to the token endpoint and obtain a bearer token without completing device authorization. This issue is fixed in version 4.0.1.
INFO
Published Date :
Nov. 5, 2026, 9:18 p.m.
Last Modified :
Nov. 5, 2026, 10:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | github | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Implement validation for the device_code parameter.
- Ensure device_code is present and valid.
- Update RequestValidator to include validate_device_code.
- Add checks similar to AuthorizationCodeGrant.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-49272.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-49272 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-49272
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-49272 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-49272 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Nov. 05, 2026
Action Type Old Value New Value Added Reference https://github.com/oauthlib/oauthlib/security/advisories/GHSA-3jp2-3mrg-2vxc Added SSVC {'id': 'CVE-2026-49272', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-11-05T21:14:28.774870Z'} -
New CVE Received by [email protected]
Nov. 05, 2026
Action Type Old Value New Value Added Description OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 3.3.0 until 4.0.1, OAuthLib's RFC 8628 device workflow does not require DeviceCodeGrant.validate_token_request to check that the device_code parameter is present and valid. A caller whose client request is accepted by the configured validator and who knows a valid client ID enabled for the device workflow can submit a missing or bogus device code to the token endpoint and obtain a bearer token without completing device authorization. This issue is fixed in version 4.0.1. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N Added CWE CWE-287 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/49xxx/CVE-2026-49272.json">CVE-2026-49272</a> Added Reference https://github.com/oauthlib/oauthlib/commit/77a5f1c8ce00da2b0b8c5f6e9cc129920085f114 Added Reference https://github.com/oauthlib/oauthlib/pull/954 Added Reference https://github.com/oauthlib/oauthlib/releases/tag/v4.0.1 Added Reference https://github.com/oauthlib/oauthlib/security/advisories/GHSA-3jp2-3mrg-2vxc