CVE-2021-29623: Uninitialized variable bug in Exiv2

Severity: low (CVSS 3.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-05-13 · updated 2026-06-17
Weakness: CWE-908

Description

Exiv2 is a C++ library and a command-line utility to read, write, delete and modify Exif, IPTC, XMP and ICC image metadata. A read of uninitialized memory was found in Exiv2 versions v0.27.3 and earlier. Exiv2 is a command-line utility and C++ library for reading, writing, deleting, and modifying the metadata of image files. The read of uninitialized memory is triggered when Exiv2 is used to read the metadata of a crafted image file. An attacker could potentially exploit the vulnerability to leak a few bytes of stack memory, if they can trick the victim into running Exiv2 on a crafted image file. The bug is fixed in version v0.27.4.

Affected products

exiv2: before 0.27.4 — fixed in 0.27.4
Fedoraproject Fedora: 33, 34

How to fix

Upgrade to a fixed version: exiv2 0.27.4. Check the vendor advisory for mitigations.

References

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