CVE-2021-34334 Denial of service due to integer overflow in loop counter

What is CVE-2021-34334?

CVE-2021-34334 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 9 Aug 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

Exiv2 is a command-line utility and C++ library for reading, writing, deleting, and modifying the metadata of image files. An infinite loop is triggered when Exiv2 is used to read the metadata of a crafted image file. An attacker could potentially exploit the vulnerability to cause a denial of service, if they can trick the victim into running Exiv2 on a crafted image file. The bug is fixed in version v0.27.5.

Weakness: CWE-835

Which versions are affected by CVE-2021-34334?

It affects 3 products.

Products include Debian Debian Linux, Exiv2 Exiv2, Fedoraproject Fedora.

How do I fix CVE-2021-34334?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-34334 being exploited?

There is no known exploitation of CVE-2021-34334 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-7215, CLEANSTART-2024-TV25386, DEBIAN-CVE-2021-34334, GHSA-hqjh-hpv8-8r9p, JLSEC-2026-1304, UBUNTU-CVE-2021-34334.