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Security Advisories

CVE-2026-103001

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-103001

Severity

6.5

Medium

CVSS V3

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Summary

PyJWT.decode() reintroduces options-dict mutation, enabling silent claim-verification bypass on dict reuse

Description

PyJWT is a Python implementation of JSON Web Token standards. From 2.11.0 through 2.13.0, PyJWT's PyJWT._merge_options() method can modify a caller-supplied mutable options mapping when verify_signature is false. If an application reuses that same mapping for a later decode() or decode_complete() call and changes verify_signature to true, the mapping can retain false values for expiration, not-before, issued-at, audience, issuer, subject, and JWT ID checks. A signed token with invalid registered claims can then be accepted without disabling signature verification, but applications that create a fresh options mapping for each call are not affected.

Affected packages


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