Cyber Resilience

CVE-2026-32135

Memory Safety in Emqx Nanomq ≤ 0.24.11

Public PoCMemory Safety
Published
20 April 2026
Modified
22 April 2026
Patch / advisory
CVSS Score v4 7.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/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
EPSS Score 0.0050 40th percentile
Risk Priority 43 floored blend · peak EPSS

Summary

CVE-2026-32135 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Emqx Nanomq. Its CVSS base score is 7.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 40th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-32135 is a heap buffer overflow vulnerability in the `uri_param_parse` function of NanoMQ's REST API. NanoMQ, an all-around Edge Messaging Platform and MQTT Broker, is affected in versions prior to 0.24.11. The issue stems from an off-by-one error during memory allocation for query parameter keys and values, which allows an attacker to write a null byte beyond the allocated buffer boundaries. This vulnerability is classified under CWE-122 (Heap-based Buffer Overflow) with a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

The vulnerability can be exploited remotely by any unauthenticated attacker with network access to the NanoMQ REST API endpoint. By sending a specially crafted HTTP request, the attacker triggers the off-by-one error, leading to a heap buffer overflow. This results in high-impact availability disruption, such as broker crashes or denial of service, without affecting confidentiality or integrity.

Mitigation is available in NanoMQ version 0.24.11, which patches the allocation logic in the `uri_param_parse` function. Security advisories and the fixing commit are detailed in the NanoMQ GitHub security advisory (GHSA-6w96-9qw7-m599), issue tracker (#2247), and the specific patch commit (69a97b3b39cc218f044f1c8896f4d3d8757bb394). Practitioners should upgrade to the patched version and review exposed REST API access.

EU & UK References

Vulnerability Data

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Versions prior to 0.24.11 have a remotely triggerable heap buffer overflow in the `uri_param_parse` function of NanoMQ's REST API. The vulnerability occurs due to an off-by-one error when allocating memory…

more

for query parameter keys and values, allowing an attacker to write a null byte beyond the allocated buffer. This can be triggered via a crafted HTTP request. Version 0.24.11 patches the issue.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-31036Same product: Emqx Nanomq
CVE-2023-34488Same product: Emqx Nanomq
CVE-2024-42648Same product: Emqx Nanomq
CVE-2024-31040Same product: Emqx Nanomq
CVE-2026-22040Same product: Emqx Nanomq
CVE-2025-66023Same product: Emqx Nanomq
CVE-2023-34494Same product: Emqx Nanomq
CVE-2024-25767Same product: Emqx Nanomq
CVE-2023-33657Same product: Emqx Nanomq
CVE-2025-59947Same product: Emqx Nanomq

Affected Assets

emqx
nanomq
≤ 0.24.11

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.4.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (including fuzzing and memory-error detectors) can discover heap overflows after they have been coded.

Input validation enforces bounds checking on data written to heap buffers, directly stopping the overflow condition from being introduced.

Security engineering principles require use of memory-safe constructs and bounds-checked allocation routines that avoid introducing heap overflows.

Memory-protection mechanisms limit the ability of a heap overflow to execute attacker-controlled code or corrupt adjacent structures.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 full match
prevents

Secure-development practices directly require bounds checking and safe memory handling that prevent heap overflows.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover heap-overflow flaws but does not prevent their introduction in code.

PR.PS-02 partial match
prevents

Timely patching removes known heap-overflow instances after they exist.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development and acceptance can detect heap overflows before release.

prevents

Secure development lifecycle mandates practices that reduce the likelihood of introducing heap overflows.

prevents

Application security requirements can specify bounds-checking and safe memory APIs that mitigate heap overflows.

prevents

Secure architecture and engineering principles include memory-safety and input-validation controls that address heap overflows.

prevents

Secure coding standards directly prescribe techniques (safe functions, bounds checks) that prevent heap-based buffer overflows.

none

Change management ensures controlled deployment of fixes for discovered heap-overflow vulnerabilities.

References