CVE-2026-66273
Apache Qpid Proton-J: Type size/count handling can lead to excessive allocation pre-authentication
A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Apache Qpid Proton-J: Type size/count handling can lead to excessive allocation pre-authentication
A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.
- Record
CVE-2026-66273- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-789
- Updated
- 2026-11-02
EUVDEUVD-2026-53055
A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.
- Record
EUVD-2026-53055- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-wr2r-m36x-734x
A pre-authentication attacker could leverage type size/count handling to cause excessive...
A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.
- Record
GHSA-wr2r-m36x-734x- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-789
- Updated
- 2026-11-02
NVD
A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.
- Record
CVE-2026-66273- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-789
- Updated
- 2026-11-02
OSV
Apache Qpid Proton-J: Type size/count handling can lead to excessive allocation pre-authentication
A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.
- Record
CVE-2026-66273- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-789
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-66273 is a high vulnerability (CVSS 7.5) in Apache Qpid Proton-j, published August 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.77%, the 55th percentile. No source names a fixed version.