What’s Vulnerable › Vulnerabilities

CVE-2021-20309

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-05-11 · updated 2026-06-17
• Weakness: CWE-369

Description

A flaw was found in ImageMagick in versions before 7.0.11 and before 6.9.12, where a division by zero in WaveImage() of MagickCore/visual-effects.c may trigger undefined behavior via a crafted image file submitted to an application using ImageMagick. The highest threat from this vulnerability is to system availability.

Affected products

• Debian Linux: 9.0
• ImageMagick: before 6.9.12; from 7.0.0-0 before 7.0.11-0 — fixed in 6.9.12, 7.0.11-0

How to fix

Upgrade to a fixed version: ImageMagick 6.9.12, 7.0.11-0. Check the vendor advisory for mitigations.

References

• https://bugzilla.redhat.com/show_bug.cgi?id=1946722
• https://lists.debian.org/debian-lts-announce/2021/06/msg00000.html
• https://lists.debian.org/debian-lts-announce/2023/05/msg00020.html
• https://bugzilla.redhat.com/show_bug.cgi?id=1946722
• https://lists.debian.org/debian-lts-announce/2021/06/msg00000.html
• https://lists.debian.org/debian-lts-announce/2023/05/msg00020.html

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