CVE-2026-121821 A vulnerability has been identified in armeria versions 0.84.0 through 1.42.0, where any-origin CORS policies do not enforce configured path
Medium 5.3
Published
Updated
Check this codebase for CVE-2026-121821 and fix it if it is affected.
What it is: CVE-2026-121821 is a medium-severity vulnerability in LY Corporation Armeria, published on 6 Nov 2026.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-121821 exists.
Affected product: LY Corporation Armeria. 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-2026-121821/ (Markdown: https://insights.sbomify.com/CVE-2026-121821/index.md)
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-121821?
CVE-2026-121821 is a medium-severity vulnerability in LY Corporation Armeria, published on 6 Nov 2026.
Official description
A vulnerability has been identified in armeria versions 0.84.0 through 1.42.0, where any-origin CORS policies do not enforce configured path restrictions, allowing an attacker-controlled website visited by an authenticated victim to read sensitive responses from excluded paths when credentials are enabled and the victim's browser sends authentication credentials.
Weakness: CWE-942
Which versions are affected by CVE-2026-121821?
How do I fix CVE-2026-121821?
No fix has been published for CVE-2026-121821 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-121821 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-121821 exists.
Sources
Also known as GHSA-386q-mrg6-jfj8.