CVE-2026-89320 HmacShaCryptor.Hash never hashes its input — returns constant HMAC_K("") for all inputs, voiding CBC-HMAC JWE integrity
High 8.8
Published
Updated
Check this codebase for CVE-2026-89320 and fix it if it is affected.
What it is: CVE-2026-89320 is a high-severity vulnerability in Eclipse KeyPont - GOSE, published on 23 Oct 2026.
Exploitation: There is no known exploitation of CVE-2026-89320 in the wild and no public exploit code.
Affected product: Eclipse KeyPont - GOSE. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2026-89320/ (Markdown: https://insights.sbomify.com/CVE-2026-89320/index.md)
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-89320?
CVE-2026-89320 is a high-severity vulnerability in Eclipse KeyPont - GOSE, published on 23 Oct 2026.
Official description
`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.
Weakness: CWE-354
Which versions are affected by CVE-2026-89320?
How do I fix CVE-2026-89320?
No fix has been published for CVE-2026-89320 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-89320 being exploited?
There is no known exploitation of CVE-2026-89320 in the wild and no public exploit code.
Sources
Also known as GHSA-h6w5-722x-2h3m.