How severe is CVE-2021-33450?

CVE-2021-33450 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-2021-33450 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33450?

CVE-2021-33450 affects Nasm Netwide Assembler. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33450?

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

When was CVE-2021-33450 published?

CVE-2021-33450 was published on 2022-07-26 and last updated on 2026-06-17.

CVE-2021-33450

CVE-2021-33450 is a medium-severity vulnerability in Nasm Netwide Assembler 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-401.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-401
Affected product: Nasm Netwide Assembler
Published: 2022-07-26
Last modified: 2026-06-17

Description

An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_calloc() in nasmlib/alloc.c.

Frequently asked questions

What is CVE-2021-33450?: An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_calloc() in nasmlib/alloc.c.
How severe is CVE-2021-33450?: CVE-2021-33450 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-2021-33450 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33450?: CVE-2021-33450 affects Nasm Netwide Assembler. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33450?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33450 published?: CVE-2021-33450 was published on 2022-07-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nasm:netwide_assembler:2.16:rc0:*:*:*:*:*:*

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