# CVE-2020-21600: Memory corruption in n/a

> A heap buffer overflow in libde265 allows attackers to execute arbitrary code or cause denial of service via a crafted file.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/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:** 16 Sep 2021
- **Updated:** 4 Aug 2024
- **Also known as:** ALPINE-CVE-2020-21600, DEBIAN-CVE-2020-21600, GHSA-jv6w-c82v-6qvw, UBUNTU-CVE-2020-21600

## What is CVE-2020-21600?

CVE-2020-21600 is a medium-severity memory corruption vulnerability in Struktur Libde265, published on 16 Sep 2021. 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

libde265 v1.0.4 contains a heap buffer overflow in the put_weighted_pred_avg_16_fallback function, which can be exploited via a crafted a file.

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

## Which versions are affected by CVE-2020-21600?

It affects 1 product.


Products: Struktur Libde265.

## How do I fix CVE-2020-21600?

Upgrade to a fixed version.

## Is CVE-2020-21600 being exploited?

There is no known exploitation of CVE-2020-21600 in the wild and no public exploit code.

## Other vulnerabilities in Struktur Libde265

- [CVE-2023-49465](https://insights.sbomify.com/CVE-2023-49465/): Memory corruption in n/a (high 8.8)
- [CVE-2023-49467](https://insights.sbomify.com/CVE-2023-49467/): Memory corruption in n/a (high 8.8)
- [CVE-2023-49468](https://insights.sbomify.com/CVE-2023-49468/): Memory corruption in n/a (high 8.8)
- [CVE-2023-27103](https://insights.sbomify.com/CVE-2023-27103/): Memory corruption in n/a (high 8.8)
- [CVE-2026-33164](https://insights.sbomify.com/CVE-2026-33164/): NULL Pointer Dereference in libde265 (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-21600 and fix it if it is affected.

What it is: CVE-2020-21600 is a medium-severity memory corruption vulnerability in Struktur Libde265, published on 16 Sep 2021. 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-2020-21600 in the wild and no public exploit code.

Affected product: Struktur Libde265. 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-2020-21600/ (Markdown: https://insights.sbomify.com/CVE-2020-21600/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-21600
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-21600
- OSV: https://osv.dev/vulnerability/CVE-2020-21600

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-21600/
Summaries are generated and may contain mistakes; the official description above is the record.