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TI-2026-20729 Aliases CVE-2026-25627

nanomq: OOB Read / Crash (DoS) via Malformed MQTT Remaining Length over WebSocket

Priority HIGH 66CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to version 0.24.8, NanoMQ’s MQTT-over-WebSocket transport can be crashed by sending an MQTT packet with a deliberately large Remaining Length in the fixed header while providing a much shorter actual payload. The code path copies Remaining Length bytes without verifying that the current receive buffer contains that many bytes, resulting in an out-of-bounds read (ASAN reports OOB / crash). This is remotely triggerable over the WebSocket listener. This issue has been patched in version 0.24.8.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0049 42nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed nanomq (nanomq): 0.24.8

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nanomqnanomqbefore 0.24.80.24.8Patch availableCNA
  • nanomq Vendornanomq Affected before 0.24.8 Fixed in 0.24.8 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:emqx:nanomq:*:*:*:*:*:*:*:*before 0.24.8Vulnerablenanomq
  • cpe:2.3:a:emqx:nanomq:*:*:*:*:*:*:*:* Versions before 0.24.8 Vulnerable ·nanomq

Remediation

  • Fix · CNA nanomq (nanomq) Fixed in 0.24.8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-25627

References

Exploit 1

Patch 2

Other 1

  • TI-2026-24672 NanoMQ has Heap Buffer Overflow in URI Parameter Parsing CVSS 4.0HIGH 7.7
  • TI-2024-28570 An access control issue in NanoMQ v0.21.10 allows attackers to bypass security… CVSS 3.1HIGH 8.8
  • TI-2026-27853 An issue in EMQ NanoMQ v.0.24.9 allows a remote attacker to cause a denial of service via… CVSS 3.1HIGH 7.5
  • TI-2026-17589 MQTT v5 Variable Byte Integer parsing out-of-bounds: get_var_integer() CVSS 3.1HIGH 7.5
  • TI-2024-20452 Null Pointer Dereference vulnerability in topic_filtern function in mqtt_parser.c in… CVSS 3.1HIGH 7.5
  • TI-2023-17307 NanoMQ 0.16.5 is vulnerable to heap-use-after-free in the nano_ctx_send function of nmq_mqtt.c. CVSS 3.1HIGH 7.5
See all 32 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences