Vulnerability · Published Aug 5, 2026 · Assigned by apache
CVE-2026-66274Apache Qpid Proton-J: Unbounded type nesting can lead to pre-authentication stackoverflow
High 7.5
In plain English
A high-severity security flaw in Apache Qpid Proton-J from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 56% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.8%top 44.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | org.apache.qpid:proton-j | 0.35.0 | GHSA-p2gc-fm5w-94jj |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Qpid Proton-J | 0 – through 0.34.1 |
Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H