Vulnerability · Published Oct 29, 2026 · Assigned by apache

CVE-2026-114230Apache Qpid Proton C: Potential authentication bypass: regular AMQP frames can be sent as SASL frames

Critical 9.8

In plain English

A critical-severity security flaw in Apache Qpid Proton C 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 0.5% (higher than 43% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.5%top 57.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

When dispatching SASL frames to authenticate the peer, Proton will also dispatch AMQP frames if they claim to be SASL frames. This allows authentication bypass. However there will be no user name set so the effects depend on how the application deals with this condition - which otherwise means that authentication has not completed yet. This issue affects Apache Qpid Proton C: through 0.40.0. Users are recommended to upgrade to version 0.41.1, which fixes the issue.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12qpid-protonno fix listedDEBIAN-CVE-2026-114230
Debian:13qpid-protonno fix listedDEBIAN-CVE-2026-114230
Debian:14qpid-protonno fix listedDEBIAN-CVE-2026-114230
Ubuntu:22.04:LTSqpid-protonno fix listedUBUNTU-CVE-2026-114230
Ubuntu:24.04:LTSqpid-protonno fix listedUBUNTU-CVE-2026-114230
Ubuntu:26.04:LTSqpid-protonno fix listedUBUNTU-CVE-2026-114230
Ubuntu:26.10qpid-protonno fix listedUBUNTU-CVE-2026-114230

Affected products (as reported)

VendorProductVersions
Apache Software Foundation Apache Qpid Proton C 0 – through 0.40.0

Weakness: CWE-305 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References