CVE-2026-67232
No exploitation reported by the sources we read.
- Published2026-09-23
- Fixed in4.2.6 · 4.1.11 · 4.0.20 · 3.13.15
- WeaknessCWE-409
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, The cowboy WebSocket options at line 117 set compress => true, enabling RFC 7692 permessage-deflate negotiation. The handler does not set max_frame_size, so cowboy's default of infinity applies. cowlib's cow_ws:parse_payload/9 calls zlib:inflate/2 on the compressed payload with no output-size limit. An attacker can negotiate permessage-deflate during the WebSocket upgrade and send a frame containing a zlib bomb (e.g. 50 KB → 5 GB). Decompression occurs in the connection process before websocket_handle/2 ever sees the MQTT bytes. An unauthenticated attacker can crash a RabbitMQ node running the Web-MQTT plugin by sending a single highly-compressed WebSocket frame (a few KB on the wire) that inflates to gigabytes in memory. The cowboy WebSocket handler decompresses the entire frame before the MQTT CONNECT packet is processed, so no credentials are required. Preconditions include rabbitmq_web_mqtt plugin enabled (not default, but common for browser clients) Network reachability to port 15675/15676 No authentication required. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.
Timeline
dates in UTC- 2026-09-2321:17CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-67232?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-67232?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD · OSV| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.2 | ≥ 4.2.0, < 4.2.6 | 4.2.6 | NVD |
| 4.1 | ≥ 4.1.0, < 4.1.11 | 4.1.11 | NVD |
| 4.0 | ≥ 4.0.0, < 4.0.20 | 4.0.20 | NVD |
| 3.13 | ≥ 3.13.0, < 3.13.15 | 3.13.15 | NVD · OSV |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
rabbitmq: rabbitmq_web_mqtt: RabbitMQ Web-MQTT plugin: Denial of Service via decompression bomb
rabbitmq-server4.2.src as a component of Red Hat Hardened Images
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update
Fix
- Update Broadcom rabbitmq server to 4.2.6 · 4.1.11 · 4.0.20 · 3.13.15
- Vendor fix Red Hat Product Security CVE-2026-67232 · 3 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
- Workaround from the vendor Red Hat Product Security CVE-2026-67232 · 4 productsThe rabbitmq_web_mqtt plugin is not enabled by default. Deployments that do not require MQTT-over-WebSockets can disable the plugin (for example, with `rabbitmq-plugins disable rabbitmq_web_mqtt`) to remove the vulnerable code path. Restricting network access to the Web-MQTT listener (by default po…
- No fix planned, says the vendor Red Hat Product Security CVE-2026-67232 · 1 productWill not fix
Advisories and patches
- github.comRelease Notes
- github.comRelease Notes
- github.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 4.0 vector
- CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Published
- 2026-09-23
- Last Modified
- 2026-10-19
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2026-67232?
Is CVE-2026-67232 actively exploited?
What is the CVSS score for CVE-2026-67232?
Running rabbitmq? Hear about its next vulnerability
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
No credit card required · No monthly cap on website lookups · 250 API requests/month
Go further
- Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
- Running this software? Vulnerability monitoring alerts you to new vulnerabilities in your products.
Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.