# CVE-2026-5476: NASA cFS cfe_tbl_passthru_codec.c CFE_TBL_ValidateCodecLoadSize integer overflow

> An integer overflow in NASA cFS table codec validation allows attackers to potentially execute code or cause denial of service on 32-bit systems.

- **Severity:** Low 2.1 (`CVSS:4.0/AV:A/AC:H/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X`)
- **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:** 3 Apr 2026
- **Updated:** 4 Apr 2026
- **Also known as:** GHSA-7x3q-gg96-9jgx

## What is CVE-2026-5476?

CVE-2026-5476 is a low-severity vulnerability in NASA cFS, published on 3 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was identified in NASA cFS up to 7.0.0 on 32-bit. Affected is the function CFE_TBL_ValidateCodecLoadSize of the file cfe/modules/tbl/fsw/src/cfe_tbl_passthru_codec.c. The manipulation leads to integer overflow. The complexity of an attack is rather high. The exploitability is told to be difficult. A fix is planned for the upcoming version milestone of the project.

Weakness: CWE-190 (Integer Overflow or Wraparound), CWE-189

## Which versions are affected by CVE-2026-5476?

It affects 1 product.


Products: Nasa Core Flight System.

## How do I fix CVE-2026-5476?

No fix has been published for CVE-2026-5476 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5476 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5476 exists.

## Other vulnerabilities in NASA cFS

- [CVE-2025-25373](https://insights.sbomify.com/CVE-2025-25373/): Missing authorization in n/a (critical 9.8)
- [CVE-2025-25371](https://insights.sbomify.com/CVE-2025-25371/): Path traversal in n/a (high 7.5)
- [CVE-2025-25372](https://insights.sbomify.com/CVE-2025-25372/): Memory corruption in n/a (high 7.5)
- [CVE-2025-25374](https://insights.sbomify.com/CVE-2025-25374/): Denial of service in n/a (high 7.5)
- [CVE-2026-5474](https://insights.sbomify.com/CVE-2026-5474/): NASA cFS CCSDS Packet Header to_lab_passthru_encode.c CFE_MSG_GetSize heap-based overflow (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5476 and fix it if it is affected.

What it is: CVE-2026-5476 is a low-severity vulnerability in NASA cFS, published on 3 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5476 exists.

Affected product: NASA cFS. 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-2026-5476/ (Markdown: https://insights.sbomify.com/CVE-2026-5476/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5476
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5476
- OSV: https://osv.dev/vulnerability/CVE-2026-5476

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5476/
Summaries are generated and may contain mistakes; the official description above is the record.