How severe is CVE-2023-33660?

CVE-2023-33660 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-33660 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-33660?

CVE-2023-33660 affects Emqx Nanomq. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-33660?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-33660 published?

CVE-2023-33660 was published on 2023-06-08 and last updated on 2026-06-17.

CVE-2023-33660

CVE-2023-33660 is a high-severity vulnerability in Emqx Nanomq with a CVSS 3.x base score of 7.5. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Emqx Nanomq
Published: 2023-06-08
Last modified: 2026-06-17

Description

A heap buffer overflow vulnerability exists in NanoMQ 0.17.2. The vulnerability can be triggered by calling the function copyn_str() in the file mqtt_parser.c. An attacker could exploit this vulnerability to cause a denial of service attack.

Frequently asked questions

What is CVE-2023-33660?: A heap buffer overflow vulnerability exists in NanoMQ 0.17.2. The vulnerability can be triggered by calling the function copyn_str() in the file mqtt_parser.c. An attacker could exploit this vulnerability to cause a denial of service attack.
How severe is CVE-2023-33660?: CVE-2023-33660 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-33660 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-33660?: CVE-2023-33660 affects Emqx Nanomq. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-33660?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-33660 published?: CVE-2023-33660 was published on 2023-06-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:emqx:nanomq:0.17.2:*:*:*:*:*:*:*

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