CVE-2026-95844

Moquette deeply nested MQTT topics can cause stack exhaustion

HIGH
7.5
CVSS Score
Published: September 23, 2026 at 04:29 PM UTC
Updated: September 29, 2026 at 02:16 AM UTC
2 products affected across 2 vendorsMoquetteMoquette

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Severity
HIGH7.5
Exploit prediction
EPSS 0.4%
SSVC
PoC

Description

Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, Moquette does not limit the depth of topic names and topic filters before processing them through recursive CTrie insertion and matching operations. A remote client can publish or subscribe with a deeply nested topic, causing a StackOverflowError that disrupts session processing and can deny service to broker clients. This issue is fixed in version 0.18.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.18.1
Affected range stops below 0.18.1, so it looks safe — our inference, not a vendor statement
v < 0.18.1
Affected range stops below 0.18.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/moquette-io/moquette/security/advisories/GHSA-5f42-97gr-vfhq
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/moquette-io/moquette/releases/tag/v0.18.1

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-674

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