Severity by source
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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
Network-reachable with no auth needed, but AC:H reflects AT:P partial-control constraint; availability-only low impact from worker restart, no scope change.
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Primary rating from Vendor (f5).
CVSS VectorVendor: f5
Lifecycle Timeline
4DescriptionCVE.org
When NGINX Plus is configured to use the Message Queuing Telemetry Transport (MQTT) filter module (ngx_stream_mqtt_filter_module), unauthenticated attackers can send requests with conditions beyond the attacker's control to cause a heap buffer over-read in the NGINX worker process, leading to a restart.
Impact: This vulnerability may allow remote unauthenticated attackers to have limited control to restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only.
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
AnalysisAI
Heap buffer over-read in NGINX Plus's MQTT filter module (ngx_stream_mqtt_filter_module) allows unauthenticated remote attackers to crash the NGINX worker process, causing a brief, recoverable service disruption. The vulnerability is data-plane only - no control plane exposure exists - and exploitation depends partly on runtime conditions outside the attacker's control, reflected by the CVSS 4.0 AT:P metric. No public exploit code or active exploitation (CISA KEV) has been identified at time of analysis; F5 has released a patch documented in advisory K000162101.
Technical ContextAI
NGINX Plus (CPE: cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:*) is F5's commercially supported, feature-extended variant of the open-source NGINX server. The vulnerable component is the optional ngx_stream_mqtt_filter_module, which operates at the stream layer to parse Message Queuing Telemetry Transport (MQTT) protocol traffic - a lightweight pub/sub messaging protocol common in IoT and telemetry pipelines. CWE-125 (Out-of-bounds Read) identifies the root cause class: the module reads beyond the allocated heap buffer boundary when processing certain MQTT client messages, triggering a segmentation fault in the NGINX worker process. Because NGINX Plus uses a master/worker process model, the master process automatically respawns crashed workers, which limits - but does not eliminate - service disruption during the crash interval.
RemediationAI
Apply the vendor-released patch by upgrading to the fixed NGINX Plus version specified in F5 advisory K000162101 (https://my.f5.com/manage/s/article/K000162101); the advisory provides exact version targets and upgrade procedures. As an immediate workaround where patching is not yet feasible, organizations that do not require MQTT proxying should remove or comment out the ngx_stream_mqtt_filter_module load directive and any related stream configuration blocks - this eliminates the attack surface entirely with no impact to non-MQTT workloads. For deployments where MQTT functionality is operationally required prior to patching, restrict network access to the MQTT stream listener port via upstream firewall ACLs or host-based packet filtering to limit exposure to known, trusted MQTT client addresses; note this reduces but does not eliminate risk from compromised trusted hosts. Confirm that the NGINX Plus master process watchdog is active and correctly configured to auto-respawn worker processes, which minimizes downtime duration if exploitation is attempted before patching.
More in Nginx Plus
View allDenial of service against HTTP/2 server implementations allows remote unauthenticated attackers to exhaust server resour
Heap buffer overflow in NGINX Plus and NGINX Open Source ngx_http_rewrite_module allows remote attackers to crash worker
Heap-based buffer overflow in NGINX Plus and NGINX Open Source affects deployments that proxy HTTP/2 or gRPC traffic ups
Heap buffer overflow in NGINX Plus and NGINX Open Source ngx_http_rewrite_module can be triggered by unauthenticated rem
Heap buffer overflow in NGINX Plus and NGINX Open Source lets unauthenticated remote attackers crash worker processes (D
Limited memory disclosure and worker-process restart in NGINX Plus and NGINX Open Source arise when the optional ngx_htt
Buffer overflow in NGINX's DAV module allows remote attackers to crash worker processes or manipulate file names outside
NGINX worker process crashes via null pointer dereference in the mail authentication module when CRAM-MD5 or APOP authen
When the NGINX Plus is configured to use the MQTT pre-read module, undisclosed requests can cause an increase in memory
NGINX Open Source and NGINX Plus contain a buffer over-read or over-write vulnerability in the ngx_http_mp4_module that
Heap buffer over-read in the ngx_http_ssi_module of NGINX Open Source and NGINX Plus lets an unauthenticated man-in-the-
Memory disclosure and denial-of-service in NGINX's SCGI and uWSGI proxy modules allow attackers with man-in-the-middle p
Same weakness CWE-125 – Out-of-bounds Read
View allSame technique Buffer Overflow
View allVendor StatusVendor
SUSE
Severity: Low| Product | Status |
|---|---|
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 16.1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5 | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE CaaS Platform 4.0 | Affected |
| SUSE Enterprise Storage 6 | Affected |
| SUSE Enterprise Storage 7 | Affected |
| SUSE Enterprise Storage 7.1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP1 | Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP2 | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP3 | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Manager Proxy 4.0 | Affected |
| SUSE Manager Proxy 4.1 | Affected |
| SUSE Manager Proxy 4.2 | Affected |
| SUSE Manager Retail Branch Server 4.0 | Affected |
| SUSE Manager Retail Branch Server 4.1 | Affected |
| SUSE Manager Retail Branch Server 4.2 | Affected |
| SUSE Manager Server 4.0 | Affected |
| SUSE Manager Server 4.1 | Affected |
| SUSE Manager Server 4.2 | Affected |
| openSUSE Leap 15.3 | Affected |
| openSUSE Leap 15.4 | Affected |
| openSUSE Leap 15.5 | Affected |
| openSUSE Leap 15.6 | Affected |
| private-registry/1.2/harbor-portal private-registry/harbor-nginx private-registry/harbor-portal suse/nginx suse/nginx:1.21 suse/rmt-nginx | Affected |
Share
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-44685
GHSA-w94h-5qpm-994v