How severe is CVE-2023-33656?

CVE-2023-33656 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-33656 being actively exploited?

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

What products are affected by CVE-2023-33656?

CVE-2023-33656 affects Emqx Nanomq. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-33656?

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

When was CVE-2023-33656 published?

CVE-2023-33656 was published on 2023-05-30 and last updated on 2026-06-17.

CVE-2023-33656

CVE-2023-33656 is a medium-severity vulnerability in Emqx Nanomq with a CVSS 3.x base score of 5.5. 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-770.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Emqx Nanomq
Published: 2023-05-30
Last modified: 2026-06-17

Description

A memory leak vulnerability exists in NanoMQ 0.17.2. The vulnerability is located in the file message.c. An attacker could exploit this vulnerability to cause a denial of service attack by causing the program to consume all available memory resources.

Frequently asked questions

What is CVE-2023-33656?: A memory leak vulnerability exists in NanoMQ 0.17.2. The vulnerability is located in the file message.c. An attacker could exploit this vulnerability to cause a denial of service attack by causing the program to consume all available memory resources.
How severe is CVE-2023-33656?: CVE-2023-33656 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-33656 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-33656?: CVE-2023-33656 affects Emqx Nanomq. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-33656?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-33656 published?: CVE-2023-33656 was published on 2023-05-30 and last updated on 2026-06-17.

References

Affected products (1)

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

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