CVE-2026-95847

Moquette client IDs can cause cross-session H2 durable-queue corruption

HIGH
7.5
CVSS Score
Published: September 23, 2026 at 04:29 PM UTC
Updated: September 28, 2026 at 03:23 PM UTC
2 products affected across 2 vendorsMoquetteMoquette

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Severity
HIGH7.5
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, H2PersistentQueue derives a session's message-map name as queue_ plus the client ID and its metadata-map name as queue_ plus the client ID plus _meta. A durable session whose client ID ends in _meta can therefore make its message map collide with another client's metadata map. The colliding sessions read and write the same H2 MVStore map with incompatible value types, which can corrupt queue head and tail data and cause message loss, misdelivery, failed queue reloads, or exposure of queued content across sessions. 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

References (4)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/moquette-io/moquette/security/advisories/GHSA-5f42-97gr-vfhq
x_refsource_MISCPatch
Source: cverecord
https://github.com/moquette-io/moquette/pull/964
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
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-99

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