CVE-2026-66274 Apache Qpid Proton-J: Unbounded type nesting can lead to pre-authentication stackoverflow
High 7.5
Published
Updated
Check this codebase for CVE-2026-66274 and fix it if it is affected.
What it is: CVE-2026-66274 is a high-severity vulnerability in Apache Qpid Proton-J, published on 5 Aug 2026.
Exploitation: There is no known exploitation of CVE-2026-66274 in the wild and no public exploit code.
Affected product: Apache Qpid Proton-J. 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-2026-66274/ (Markdown: https://insights.sbomify.com/CVE-2026-66274/index.md)
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-66274?
CVE-2026-66274 is a high-severity vulnerability in Apache Qpid Proton-J, published on 5 Aug 2026.
Official description
A pre-authentication attacker could leverage type nesting to cause a StackOverflowError potentially leading to denial of service.
This issue affects Apache Qpid Proton-J: through 0.34.1.
Users are recommended to upgrade to version 0.35.0, which fixes the issue.
Weakness: CWE-674
Which versions are affected by CVE-2026-66274?
It affects 1 product.
Products include Apache Qpid Proton-J.
How do I fix CVE-2026-66274?
Upgrade to a fixed version.
Is CVE-2026-66274 being exploited?
There is no known exploitation of CVE-2026-66274 in the wild and no public exploit code.
Other vulnerabilities in Apache Qpid Proton-J
- CVE-2026-66257 Apache Qpid Proton-J: Unbounded symbol value caching can lead to pre-authentication resource exhaustion
- CVE-2026-66273 Apache Qpid Proton-J: Type size/count handling can lead to excessive allocation pre-authentication
- CVE-2018-17187 Improper Certificate Validation in proton-j
- CVE-2026-66275 Apache Qpid Proton-J: Incoming session flow control window can be exceeded
- CVE-2026-66276 Apache Qpid Proton-J: Unbounded disposition range handling can lead to denial of service
Sources
Also known as CLEANSTART-2026-YX84195, GHSA-p2gc-fm5w-94jj.