CVE-2024-53861lowCWE-697

CVE-2024-53861: low-severity vulnerability in jpadilla pyjwt

Issuer field partial matches allowed in pyjwt

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 2.2epss 0.8%
pyjwt is a JSON Web Token implementation in Python. An incorrect string comparison is run for `iss` checking, resulting in `"acb"` being accepted for `"_abc_"`. This is a bug introduced in version 2.10.0: checking the "iss" claim changed from `isinstance(issuer, list)` to `isinstance(issuer, Sequence)`. Since str is a Sequnce, but not a list, `in` is also used for string comparison. This results in `if "abc" not in "__abcd__":` being checked instead of `if "abc" != "__abc__":`. Signature checks are still present so real world impact is likely limited to denial of service scenarios. This issue has been patched in version 2.10.1. All users are advised to upgrade. There are no known workarounds for this vulnerability.
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N
Affected products
jpadilla · pyjwt
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