GHSA-75c5-xw7c-p5pm: pyjwt (CVE-2024-53861)

Package	Ecosystem	Affected	Fixed in
pyjwt	PyPI	>=2.10.0, <2.10.1	2.10.1

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

PyJWT versions 2.10.0 up to but not including 2.10.1 check the "iss" claim incorrectly: a string comparison uses substring matching, so an issuer that only partially matches the expected value can be accepted. For example, "acb" is accepted where "_abc_" is expected. The attacker must already be able to produce a token with a valid signature, so the source describes the real-world impact as limited. Upgrade to PyJWT 2.10.1.

Written 5 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
2.2	Low	3.1	CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0083, the 57th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:35 UTC First seen by agentprime
31 Oct 2026, 14:35 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.