CVE-2026-49272: high-severity vulnerability in oauthlib
OAuthLib: Bearer token can be retrieved as long as client knows a valid client ID for device workflow
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.5epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N
Affected products
oauthlib · oauthlibRelated CVEs — oauthlib
In the same product, most dangerous first.
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