# CVE-2026-115504: CFITSIO through 4.7.0 Out-of-Bounds Write via ffgcls2 in getcols.c


- **Severity:** High 8.5 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 22 Oct 2026
- **Updated:** 29 Oct 2026
- **Also known as:** AZL-110540, DEBIAN-CVE-2026-115504, ECHO-1240-5fc7-729a, GHSA-wjcj-f49x-x56c, UBUNTU-CVE-2026-115504

## What is CVE-2026-115504?

CVE-2026-115504 is a high-severity vulnerability in HEASARC cfitsio, published on 22 Oct 2026. 

### Official description

CFITSIO through 4.7.0 contains an out-of-bounds write vulnerability in ffgcls2() in getcols.c that trusts attacker-controlled heap descriptor lengths for variable-length string columns. Attackers can supply a crafted FITS file that overflows a fixed 28,800-byte stack buffer and the caller's string array, enabling arbitrary code execution.

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

## Which versions are affected by CVE-2026-115504?


## How do I fix CVE-2026-115504?

Upgrade to a fixed version.

## Is CVE-2026-115504 being exploited?

There is no known exploitation of CVE-2026-115504 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-115504 and fix it if it is affected.

What it is: CVE-2026-115504 is a high-severity vulnerability in HEASARC cfitsio, published on 22 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-115504 in the wild and no public exploit code.

Affected product: HEASARC cfitsio. 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-2026-115504/ (Markdown: https://insights.sbomify.com/CVE-2026-115504/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-115504
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-115504
- OSV: https://osv.dev/vulnerability/CVE-2026-115504

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-115504/
Summaries are generated and may contain mistakes; the official description above is the record.