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).
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
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | qpid-proton | no fix listed | DEBIAN-CVE-2026-114230 |
| Debian:13 | qpid-proton | no fix listed | DEBIAN-CVE-2026-114230 |
| Debian:14 | qpid-proton | no fix listed | DEBIAN-CVE-2026-114230 |
| Ubuntu:22.04:LTS | qpid-proton | no fix listed | UBUNTU-CVE-2026-114230 |
| Ubuntu:24.04:LTS | qpid-proton | no fix listed | UBUNTU-CVE-2026-114230 |
| Ubuntu:26.04:LTS | qpid-proton | no fix listed | UBUNTU-CVE-2026-114230 |
| Ubuntu:26.10 | qpid-proton | no fix listed | UBUNTU-CVE-2026-114230 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| 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