# CVE-2020-24439: Acrobat Reader DC for macOS Signature Validation Bypass

> Attackers can bypass signature validation in Acrobat Reader DC for macOS, though practical impact is minimal.

- **Severity:** Low 2.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 5 Nov 2020
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-h5w3-mrcg-5p55

## What is CVE-2020-24439?

CVE-2020-24439 is a low-severity vulnerability in Adobe Acrobat, published on 5 Nov 2020. 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

Acrobat Reader DC for macOS versions 2020.012.20048 (and earlier), 2020.001.30005 (and earlier) and 2017.011.30175 (and earlier) are affected by a security feature bypass. While the practical security impact is minimal, a defense-in-depth fix has been implemented to further harden the Adobe Reader update process.

Weakness: CWE-347 (Improper Verification of Cryptographic Signature)

## Which versions are affected by CVE-2020-24439?

It affects 4 products.


Products: Adobe Acrobat, Adobe Acrobat Dc, Adobe Acrobat Reader, Adobe Acrobat Reader Dc.

## How do I fix CVE-2020-24439?

No fix has been published for CVE-2020-24439 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-24439 being exploited?

There is no known exploitation of CVE-2020-24439 in the wild and no public exploit code.

## Other vulnerabilities in Adobe Acrobat

- [CVE-2021-28550](https://insights.sbomify.com/CVE-2021-28550/): Adobe Acrobat and Reader Use-After-Free (critical 9.6, exploited in the wild)
- [CVE-2021-21017](https://insights.sbomify.com/CVE-2021-21017/): Adobe Acrobat and Reader Heap-based Buffer Overflow (high 8.8, exploited in the wild)
- [CVE-2014-0546](https://insights.sbomify.com/CVE-2014-0546/): Adobe Reader and Acrobat Sandbox Bypass (high 8.8, exploited in the wild)
- [CVE-2014-0496](https://insights.sbomify.com/CVE-2014-0496/): Adobe Reader and Acrobat Use-After-Free (high 8.8, exploited in the wild)
- [CVE-2013-3346](https://insights.sbomify.com/CVE-2013-3346/): Adobe Reader and Acrobat Memory Corruption (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-24439 and fix it if it is affected.

What it is: CVE-2020-24439 is a low-severity vulnerability in Adobe Acrobat, published on 5 Nov 2020. 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-2020-24439 in the wild and no public exploit code.

Affected product: Adobe Acrobat. 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-2020-24439/ (Markdown: https://insights.sbomify.com/CVE-2020-24439/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-24439
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-24439
- OSV: https://osv.dev/vulnerability/CVE-2020-24439

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-24439/
Summaries are generated and may contain mistakes; the official description above is the record.