CVE-2026-67551: Apache Qpid Proton Dotnet: Type size/count handling can lead to excessive allocation pre-authentication

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-05 · updated 2026-10-24
Weakness: CWE-789

Description

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-Dotnet: through 1.0.0. Users are recommended to upgrade to version 1.1.0, which fixes the issue.

Affected products

Apache Software Foundation Apache Qpid Proton Dotnet: before 1.1.0 — fixed in 1.1.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Qpid Proton Dotnet 1.1.0. Check the vendor advisory for mitigations.

References

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