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Luu, T.J.

GHSA-x33g-cr3x-6449: PyJWT accepts inconsistent OKP x/d JWKs, causing public/private key identity confusion

mediumvulnerability

security

Source: GitHub Advisory DatabaseOctober 5, 2026CVE-2026-102275

Summary

PyJWT has a vulnerability where it accepts OKP private keys (a type of cryptographic key used in EdDSA signatures) that are internally inconsistent: the declared public key component doesn't match the one derived from the private key component. This allows an attacker to create a malicious key where PyJWT performs cryptographic operations with the attacker's private key while the key appears to belong to a legitimate user, potentially allowing stolen access tokens to be misused in DPoP (proof-of-possession) integrations.

Solution / Mitigation

A correct import should derive the public key from the private key component and reject the JWK when it does not match the supplied public key component, as stated in the source: 'A correct import should derive the public key from `d` and reject the JWK when it does not equal the supplied `x`.' However, no specific patched version or code fix is provided in the source text.