# CVE-2024-27929: Use After Free in SixLabors.ImageSharp

> A heap-use-after-free flaw in SixLabors.ImageSharp allows attackers to disclose information via specially crafted PNG images.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 5 Mar 2024
- **Updated:** 2 Aug 2024
- **Also known as:** ECHO-4d13-a9eb-08c2, GHSA-65x7-c272-7g7r

## What is CVE-2024-27929?

CVE-2024-27929 is a high-severity use after free vulnerability in SixLabors ImageSharp, published on 5 Mar 2024. 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

ImageSharp is a managed, cross-platform, 2D graphics library. A heap-use-after-free flaw was found in ImageSharp's InitializeImage() function of PngDecoderCore.cs file. This vulnerability is triggered when an attacker passes a specially crafted PNG image file to ImageSharp for conversion, potentially leading to information disclosure. This issue has been patched in versions 3.1.3 and 2.1.7.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-27929?

4 open source packages ship an affected version, including SixLabors.ImageSharp. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `SixLabors.ImageSharp` | NuGet | All versions | 2.1.7 |
| `SixLabors.ImageSharp` | NuGet | All versions | 2.1.7 |
| `SixLabors.ImageSharp` | NuGet | From 3.0.0 | 3.1.3 |
| `SixLabors.ImageSharp` | NuGet | From 3.0.0 | 3.1.3 |

Products: Sixlabors Imagesharp.

## How do I fix CVE-2024-27929?

Upgrade SixLabors.ImageSharp to a fixed version for your release line: 2.1.7 or 3.1.3.

## Is CVE-2024-27929 being exploited?

There is no known exploitation of CVE-2024-27929 in the wild and no public exploit code.

## Other vulnerabilities in SixLabors ImageSharp

- [CVE-2026-106110](https://insights.sbomify.com/CVE-2026-106110/): ImageSharp: TIFF CCITT T4 encoder can write past its compressed output buffer (high 7.5)
- [CVE-2026-106112](https://insights.sbomify.com/CVE-2026-106112/): ImageSharp: ICC LUT16 output channel count can write beyond Vector4 (high 7.5)
- [CVE-2026-106113](https://insights.sbomify.com/CVE-2026-106113/): ImageSharp: HistogramEqualization uses an unvalidated luminance as an unchecked histogram index (high 7.5)
- [CVE-2026-106115](https://insights.sbomify.com/CVE-2026-106115/): ImageSharp: TIFF CCITT T6 encoder writes beyond an undersized output buffer (high 7.5)
- [CVE-2026-106117](https://insights.sbomify.com/CVE-2026-106117/): ImageSharp: CCITT fax decompression (T4/Modified Huffman): unbounded WriteBits overflows strip buffer — heap OOB write in SixLabors.ImageSharp (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-27929 and fix it if it is affected.

What it is: CVE-2024-27929 is a high-severity use after free vulnerability in SixLabors ImageSharp, published on 5 Mar 2024. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2024-27929 in the wild and no public exploit code.

Affected packages and fixed versions:
- SixLabors.ImageSharp (NuGet): affected all versions; fixed in 2.1.7
- SixLabors.ImageSharp (NuGet): affected all versions; fixed in 2.1.7
- SixLabors.ImageSharp (NuGet): affected from 3.0.0; fixed in 3.1.3
- SixLabors.ImageSharp (NuGet): affected from 3.0.0; fixed in 3.1.3

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-27929/ (Markdown: https://insights.sbomify.com/CVE-2024-27929/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-27929
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-27929
- OSV: https://osv.dev/vulnerability/CVE-2024-27929

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-27929/
Summaries are generated and may contain mistakes; the official description above is the record.