# CVE-2020-24658: Security feature bypass in n/a

> Arm Compiler 5 stack protection fails to detect corruption if both guard and reference values are overwritten, bypassing security checks.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-w56g-cw97-958x

## What is CVE-2020-24658?

CVE-2020-24658 is a high-severity vulnerability in n/a, published on 24 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Arm Compiler 5 through 5.06u6 has an error in a stack protection feature designed to help spot stack-based buffer overflows in local arrays. When this feature is enabled, a protected function writes a guard value to the stack prior to (above) any vulnerable arrays in the stack. The guard value is checked for corruption on function return; corruption leads to an error-handler call. In certain circumstances, the reference value that is compared against the guard value is itself also written to the stack (after any vulnerable arrays). The reference value is written to the stack when the function runs out of registers to use for other temporary data. If both the reference value and the guard value are written to the stack, then the stack protection will fail to spot corruption when both values are overwritten with the same value. For both the reference value and the guard value to be corrupted, there would need to be both a buffer overflow and a buffer underflow in the vulnerable arrays (or some other vulnerability that causes two separated stack entries to be corrupted).

Weakness: CWE-787 (Out-of-bounds Write), CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2020-24658?

It affects 1 product.


Products: Arm Arm Compiler.

## How do I fix CVE-2020-24658?

No fix has been published for CVE-2020-24658 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-24658 being exploited?

There is no known exploitation of CVE-2020-24658 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2022-43701](https://insights.sbomify.com/CVE-2022-43701/): Insecure directory permissions on installer files (high 7.8)
- [CVE-2022-43702](https://insights.sbomify.com/CVE-2022-43702/): Incomplete verification of installation file signature (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-24658 and fix it if it is affected.

What it is: CVE-2020-24658 is a high-severity vulnerability in n/a, published on 24 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-24658 in the wild and no public exploit code.

Affected product: n/a. 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-2020-24658/ (Markdown: https://insights.sbomify.com/CVE-2020-24658/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-24658
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-24658
- OSV: https://osv.dev/vulnerability/CVE-2020-24658

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-24658/
Summaries are generated and may contain mistakes; the official description above is the record.