CVE-2021-3476

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-30 · updated 2026-06-17
Weakness: CWE-190

Description

A flaw was found in OpenEXR's B44 uncompression functionality in versions before 3.0.0-beta. An attacker who is able to submit a crafted file to OpenEXR could trigger shift overflows, potentially affecting application availability.

Affected products

Debian Linux: 9.0, 10.0
AcademySoftwareFoundation openexr: before 2.4.3; from 2.5.0 before 2.5.4 — fixed in 2.4.3, 2.5.4

How to fix

Upgrade to a fixed version: AcademySoftwareFoundation openexr 2.4.3, 2.5.4. Check the vendor advisory for mitigations.

References

https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=24787
https://bugzilla.redhat.com/show_bug.cgi?id=1939145
https://lists.debian.org/debian-lts-announce/2021/07/msg00001.html
https://lists.debian.org/debian-lts-announce/2022/12/msg00022.html
https://security.gentoo.org/glsa/202107-27
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=24787
https://bugzilla.redhat.com/show_bug.cgi?id=1939145
https://lists.debian.org/debian-lts-announce/2021/07/msg00001.html
https://lists.debian.org/debian-lts-announce/2022/12/msg00022.html
https://security.gentoo.org/glsa/202107-27

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