Public vulnerability disclosure

CVE-2026-89320

HmacShaCryptor.Hash never hashes its input — returns constant HMAC_K("") for all inputs, voiding CBC-HMAC JWE integrity

publishedCWE-354

`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.

Technical severity8.8 highCVSS 4.0 · CNA: eclipse
Published2026-10-23Source updated 2026-11-02
Collected2026-11-022 attributed sources

Fixes and workarounds

No remediation reported in collected sources.

Missing remediation information is not evidence that no patch exists.

Affected products and versions

Affected products, source version ranges and reporting authorities
ProductVersionsAuthority
Eclipse KeyPont - GOSE
Eclipse Foundation
github.com/ThalesGroup/gose
≥ 0.9.0; ≤ 0.13.0-rc1 (affected, semver)
Other versions: unaffected
CNA: eclipse
Eclipse KeyPont - GOSE
Eclipse Foundation
github.com/eclipse-keypont/gose
≥ 0; < 1.0.0-rc1 (affected, semver)
Other versions: unaffected
CNA: eclipse

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / scoreVectorAuthority
4.0 / 8.8
high
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:NCNA: eclipse

Exploit evidence

References