# CVE-2026-124001: ION-DTN 2.2.1b-4.2.0 Integer Overflow Heap Corruption via DGR


- **Severity:** Critical 9.2 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 9 Nov 2026
- **Updated:** 9 Nov 2026
- **Also known as:** GHSA-rcqq-5qmv-7fxp

## What is CVE-2026-124001?

CVE-2026-124001 is a critical vulnerability in nasa-jpl ION-DTN, published on 9 Nov 2026. 

### Official description

NASA JPL ION-DTN 2.2.1b through 4.2.0 contains an integer overflow vulnerability in the Datagram Retransmission (DGR) convergence layer that allows attackers to corrupt heap memory by sending a maliciously crafted 64-bit svcDataLength value that wraps a 32-bit allocation size calculation. Attackers can exploit the dgr_receive API's unchecked memcpy operation using synthetic datagrams or DGR traffic over internal IPC or custom transports to trigger an out-of-bounds write, leading to denial of service or potential remote code execution.

Weakness: CWE-787 (Out-of-bounds Write), CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-124001?


## How do I fix CVE-2026-124001?

No fix has been published for CVE-2026-124001 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-124001 being exploited?

There is no known exploitation of CVE-2026-124001 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-124001 and fix it if it is affected.

What it is: CVE-2026-124001 is a critical vulnerability in nasa-jpl ION-DTN, published on 9 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-124001 in the wild and no public exploit code.

Affected product: nasa-jpl ION-DTN. 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-2026-124001/ (Markdown: https://insights.sbomify.com/CVE-2026-124001/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-124001
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-124001
- OSV: https://osv.dev/vulnerability/CVE-2026-124001

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-124001/
Summaries are generated and may contain mistakes; the official description above is the record.