CVE-2021-33454

MEDIUMNVD 5.55.5—

5.5

An issue was discovered in yasm version 1.3.0. There is a NULL pointer dereference in yasm_expr_get_intnum() in libyasm/expr.c.

CVSS v3: 5.5
EG Score: 5.5(medium)
EPSS: 16.3%
KEV: Not listed

Published

July 26, 2022

Last Modified

November 21, 2024

References (4)

cve@mitrehttps://gist.github.com/Clingto/bb632c0c463f4b2c97e4f65f751c5e6d
cve@mitrehttps://github.com/yasm/yasm/issues/166
af854a3a-2127-422b-91ae-364da2661108https://gist.github.com/Clingto/bb632c0c463f4b2c97e4f65f751c5e6d
af854a3a-2127-422b-91ae-364da2661108https://github.com/yasm/yasm/issues/166

Vendor Advisories for CVE-2021-33454(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

CVE-2021-33454
Microsoft Security Response Center (MSRC)
CVE-2021-33454

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-476NULL Pointer Dereference

Data Freshness Timeline

(refreshed 12× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-04 13:10 UTCepss_batch
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Frequently asked(5)

What is CVE-2021-33454?

CVE-2021-33454 is a medium vulnerability published on July 26, 2022. An issue was discovered in yasm version 1.3.0. There is a NULL pointer dereference in yasmexprget_intnum() in libyasm/expr.c.

When was CVE-2021-33454 disclosed?

CVE-2021-33454 was first published in the National Vulnerability Database on July 26, 2022, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-33454 actively exploited?

CVE-2021-33454 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 16.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-33454?

CVE-2021-33454 has a CVSS v3 base score of 5.5 (NVD).

How do I remediate CVE-2021-33454?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-33454, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-33454

Published

Last Modified

References (4)

Vendor Advisories for CVE-2021-33454(1)

Weakness Classification(1)

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-33454?

Same vendor

Same CWE

CVE-2021-33454

📅 Published

🔄 Last Modified

🔗 References (4)

📣 Vendor Advisories for CVE-2021-33454(1)

Weakness Classification(1)

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-33454?

🔗 Related CVEs(same vendor + same CWE)

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Last Modified

References (4)

Vendor Advisories for CVE-2021-33454(1)

Frequently asked(5)

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