How severe is CVE-2021-20243?

CVE-2021-20243 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-2021-20243 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20243?

CVE-2021-20243 primarily affects Imagemagick. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20243?

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

When was CVE-2021-20243 published?

CVE-2021-20243 was published on 2021-03-09 and last updated on 2026-06-17.

CVE-2021-20243

CVE-2021-20243 is a medium-severity vulnerability in Imagemagick 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-369.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-369
Affected product: Imagemagick
Published: 2021-03-09
Last modified: 2026-06-17

Description

A flaw was found in ImageMagick in MagickCore/resize.c. An attacker who submits a crafted file that is processed by ImageMagick could trigger undefined behavior in the form of math division by zero. The highest threat from this vulnerability is to system availability.

Frequently asked questions

What is CVE-2021-20243?: A flaw was found in ImageMagick in MagickCore/resize.c. An attacker who submits a crafted file that is processed by ImageMagick could trigger undefined behavior in the form of math division by zero. The highest threat from this vulnerability is to system availability.
How severe is CVE-2021-20243?: CVE-2021-20243 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-2021-20243 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20243?: CVE-2021-20243 primarily affects Imagemagick. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20243?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20243 published?: CVE-2021-20243 was published on 2021-03-09 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:imagemagick:imagemagick:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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Other CWE-369 (Divide By Zero) vulnerabilities

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