# CVE-2019-6977: Memory corruption in n/a

> Heap-based buffer overflow in LibGD allows attackers to execute arbitrary code or cause denial of service via crafted image data.

- **Severity:** High 8.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 27 Jan 2019
- **Updated:** 4 Aug 2024
- **Also known as:** ALPINE-CVE-2019-6977, DEBIAN-CVE-2019-6977, GHSA-3jrx-xgc5-h2f9, SUSE-SU-2019:0449-1, UBUNTU-CVE-2019-6977, openSUSE-SU-2024:11852-1

## What is CVE-2019-6977?

CVE-2019-6977 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 27 Jan 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

gdImageColorMatch in gd_color_match.c in the GD Graphics Library (aka LibGD) 2.2.5, as used in the imagecolormatch function in PHP before 5.6.40, 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.1, has a heap-based buffer overflow. This can be exploited by an attacker who is able to trigger imagecolormatch calls with crafted image data.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2019-6977?

It affects 5 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `php5` | SUSE:Linux Enterprise Module for Web and Scripting 12 | All versions | 5.5.14-109.48.1 |
| `php5` | SUSE:Linux Enterprise Software Development Kit 12 SP3 | All versions | 5.5.14-109.48.1 |
| `php5` | SUSE:Linux Enterprise Software Development Kit 12 SP4 | All versions | 5.5.14-109.48.1 |
| `perl-GD` | openSUSE:Tumbleweed | All versions | 2.76-1.1 |

Products: Canonical Ubuntu Linux, Debian Debian Linux, Libgd Libgd, Netapp Storage Automation Store, Php Php.

## How do I fix CVE-2019-6977?

Upgrade to a fixed version.

## Is CVE-2019-6977 being exploited?

There is no known exploitation of CVE-2019-6977 in the wild and no public exploit code.

Public exploit code:

- PHP 7.2 - 'imagecolormatch()' Out of Band Heap Write (exploitdb)
- CVE-2022-31626, CVE-2024-2961, CVE-2019-6977, PHP security research (github_poc): https://github.com/HORKimhab/CVE-2022-31626-CVE-2024-2961-CVE-2019-6977

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-6977 and fix it if it is affected.

What it is: CVE-2019-6977 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 27 Jan 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-6977 in the wild and no public exploit code.

Affected product: Canonical Ubuntu Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2019-6977/ (Markdown: https://insights.sbomify.com/CVE-2019-6977/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-6977
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-6977
- OSV: https://osv.dev/vulnerability/CVE-2019-6977

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-6977/
Summaries are generated and may contain mistakes; the official description above is the record.