CVE-2026-33217
NATS allows MQTT clients to bypass ACL checks
02 Description
NATS allows MQTT clients to bypass ACL checks
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.26% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 18.1% of scored records. A rank, not a probability.
- NVD base score
- 6.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- NVD analysis status
- Modified. NVD last modified this record on 2026-09-09.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-03-25 19:43Z7 MO AGO
- Last updated
- 2026-09-09 12:04Z1 MO AGO
- Reserved
- 2026-03-17
- Assigning CNA
- GitHub_M
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.1)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
- Weaknesses
- Data version
- 5.2
- Document digest
- 3d89181421a0d819776961bda2fdd7c99ad6b1d948b5bc7ae781f6eb439cdf14
05 Affected products
06 References
- github.comhttps://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5
- advisories.nats.iohttps://advisories.nats.io/CVE/secnote-2026-07.txt
- access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-33217
- bugzilla.redhat.comRHBZ#2451446https://bugzilla.redhat.com/show_bug.cgi?id=2451446
- security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33217.json
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:22347
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:23345
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:21769
07 Fixed in
Debian 12
- nats-server No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- nats-server No fix yet
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- nats-server Fixed in 2.12.6-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- nats-server No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 25.10
- nats-server No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 26.10
- nats-server No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 26.04 LTS
- nats-server No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.