CVE-2024-53861

Issuer field partial matches allowed in pyjwt

State
Published
Severity
2.2 Low
Published
Nov 29, 2024
Updated
Dec 2, 2024
Reserved
Nov 22, 2024

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.12.2 LowCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:NGitHub_M

Weaknesses

Affected Products

ProductVersions
pyjwtjpadilla
  • = 2.10.0Affected

References

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