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

Summary PyJWT.decode/decodecomplete mutates a caller-supplied options dict in place whenever verifysignature is falsy, adding verifyexp/verifynbf/verifyiat/verifyaud/verifyiss/verifysub/verifyjti keys directly onto that object. If application code reuses the same options dict across calls a confi...

CVE-2026-103001

The PyJWT library (versions 2.11.0 through 2.13.0 ) contains a vulnerability where the PyJWT._merge_options() method modifies a caller-supplied mutable options mapping when verify_signature is set to false . If an application reuses this same mapping for subsequent decode() or decode_complete() c...