Answer in brief
CVE-2026-49264 records a Medium severity (CVSS 6.1) vulnerability in OAuthLib: Unsafe JSONP callback injection in RevocationEndpoint allows arbitrary JavaScript response generation. The current sources do not mark it as known exploited. The current feed maps oauthlib/oauthlib (generic), oauthlib (pip), oauthlib (pypi). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps oauthlib/oauthlib (generic), oauthlib (pip), oauthlib (pypi). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| oauthlib/oauthlibgeneric | >=0.6.1 <4.0.0 | 4.0.0 |
| oauthlibpip | >=0.6.1,<=3.3.1 | 4.0.0 |
| oauthlibpypi | >=0.6.1 <4.0.0 | 4.0.0 |
Published upstream
Oct 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 29, 2026
OAuthLib is an implementation of the OAuth request-signing logic for Python 3.6+. From 0.6.1 until 4.0.0, OAuthLib's RevocationEndpoint in oauthlib/oauth2/rfc6749/endpoints/revocation.py reflects an unvalidated callback request parameter into success and error response bodies when enable_jsonp=True. The callback can come from the query string or request body and is used without restricting it to a legal JavaScript function name. A browser application that loads the revocation response as trusted JSONP and permits attacker influence over callback can therefore execute attacker-controlled JavaScript in the including application's origin, with access to its DOM and script-accessible data. The feature is disabled by default, so only deployments that explicitly enable JSONP are affected. This issue is fixed in version 4.0.0.
Quoted source text, attributed separately from HOL analysis.