CVE-2026-89320 — HmacShaCryptor.Hash never hashes its input — returns constant HMAC_K("") for all inputs, voiding CBC-HMAC JWE integrity
`HmacShaCryptor.Hash` never hashed its input. For any input it returned `HMAC_K("")` — the MAC of the empty message under the key. Every AES-CBC-HMAC JWE produced or verified by…
Published: 2026-10-23 · CVSS: 8.8 · CVSS 4.0
`HmacShaCryptor.Hash` never hashed its input. For any input it returned `HMAC_K("")` — the MAC of the empty message under the key. Every AES-CBC-HMAC JWE produced or verified by gose therefore carried an authentication tag that is constant per key and independent of the message, removing ciphertext integrity entirely.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7