How severe is CVE-2026-25627?

CVE-2026-25627 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-25627 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-25627?

CVE-2026-25627 affects Emqx Nanomq. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-25627?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-25627 have an EU (EUVD) identifier?

Yes. CVE-2026-25627 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17195.

When was CVE-2026-25627 published?

CVE-2026-25627 was published on 2026-03-30 and last updated on 2026-06-17.

CVE-2026-25627

CVE-2026-25627 is a medium-severity vulnerability in Emqx Nanomq with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17195
Weakness: CWE-125
Affected product: Emqx Nanomq
Published: 2026-03-30
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-25627?: 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.
How severe is CVE-2026-25627?: CVE-2026-25627 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-25627 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-25627?: CVE-2026-25627 affects Emqx Nanomq. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-25627?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-25627 have an EU (EUVD) identifier?: Yes. CVE-2026-25627 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17195.
When was CVE-2026-25627 published?: CVE-2026-25627 was published on 2026-03-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:emqx:nanomq:*:*:*:*:*:*:*:*

More vulnerabilities in Emqx Nanomq

CVE-2025-59947 — Critical (CVSS 9.0): NanoMQ is a messaging broker/bus for IoT Edge & SDV. Versions prior to 0.24.4 have a buffer overflow case while the…
CVE-2024-42655 — High (CVSS 8.8): An access control issue in NanoMQ v0.21.10 allows attackers to bypass security restrictions and access sensitive system…
CVE-2023-34488 — High (CVSS 7.8): NanoMQ 0.17.5 has a one-byte heap-based buffer over-read in the conn_handler function of mqtt_parser.c when it…
CVE-2026-32135 — High (CVSS 7.5): NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Versions prior to 0.24.11 have a remotely…
CVE-2026-21888 — High (CVSS 7.5): NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. MQTT v5 Variable Byte Integer parsing…
CVE-2024-48077 — High (CVSS 7.5): NanoMQ v0.22.7 is vulnerable to Denial of Service (DoS) due to improper resource throttling. A crafted sequence of…

All CVEs affecting Emqx Nanomq →

Other CWE-125 (Out-of-bounds Read) vulnerabilities

CVE-2026-24826 — Critical (CVSS 10.0): Out-of-bounds Write, Divide By Zero, NULL Pointer Dereference, Use of Uninitialized Resource, Out-of-bounds Read,…
CVE-2024-22004 — Critical (CVSS 10.0): Due to length check, an attacker with privilege access on a Linux Nonsecure operating system can trigger a…
CVE-2021-41556 — Critical (CVSS 10.0): sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that…
CVE-2021-21777 — Critical (CVSS 10.0): An information disclosure vulnerability exists in the Ethernet/IP UDP handler functionality of EIP Stack Group OpENer…
CVE-2017-14451 — Critical (CVSS 10.0): An exploitable out-of-bounds read vulnerability exists in libevm (Ethereum Virtual Machine) of CPP-Ethereum. A…
CVE-2013-0767 — Critical (CVSS 10.0): The nsSVGPathElement::GetPathLengthScale function in Mozilla Firefox before 18.0, Firefox ESR 10.x before 10.0.12 and…

Browse all CWE-125 (Out-of-bounds Read) vulnerabilities →