Oauthlib : Unsafe JSONP callback injection
Affects oauthlibSource GCVE Database
Not known to be exploited · CVSS 6.1 Medium : upgrade to 4.0.0 when convenient.
Data as of 13 Nov 2026, 23:54 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 14% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.0.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 29 Sep 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 14 Nov 2026.
What to do
Upgrade oauthlib to 4.0.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PyPIoauthlib | Affected
| Fixed in
|
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AI-suggested
A fix is available in oauthlib version 4.0.0. Users should upgrade to version 4.0.0 or later to remediate this vulnerability. If upgrading is not immediately possible, disabling the enable_jsonp feature will prevent exploitation. No other mitigations are specifically recommended by the vendor advisory.
Description
Oauthlib's RevocationEndpoint with JSONP enabled (enable_jsonp=True) reflects the user-supplied callback parameter directly into JavaScript responses without validation. This allows attackers who can influence the callback parameter to inject arbitrary JavaScript code into the response, leading to unsafe JSONP usage. The vulnerability affects oauthlib versions from 0.6.1 up to but not including 4.0.0. The issue is fixed in version 4.0.0.
References
- github.com/oauthlib/oauthlib/security/advisories/GHSA-hj66-6f7g-4r5v (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-49264 (opens in a new tab)
- github.com/oauthlib/oauthlib/pull/951 (opens in a new tab)
- github.com/oauthlib/oauthlib/commit/c888359f3c42bec235b2c5caab2069c9ed62457c (opens in a new tab)
- github.com/oauthlib/oauthlib (opens in a new tab)
- github.com/pypa/advisory-database/tree/main/vulns/oauthlib/PYSEC-2026-4113.yaml (opens in a new tab)