# CVE-2026-124747: Busybox: heap buffer overflow in wget ftp resume when the resume offset exceeds the reported file size


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 10 Nov 2026
- **Updated:** 10 Nov 2026
- **Also known as:** GHSA-7mcj-w43r-5jqf, UBUNTU-CVE-2026-124747

## What is CVE-2026-124747?

CVE-2026-124747 is a high-severity vulnerability in Red Hat Enterprise Linux 6, published on 10 Nov 2026. 

### Official description

A flaw was found in BusyBox. When resuming a download over File Transfer Protocol (FTP), the wget utility fails to verify that the resume offset does not exceed the file size reported by the server, resulting in an integer calculation error. A malicious FTP server or an on-path network attacker can exploit this issue by returning crafted file size metadata, triggering a heap-based buffer overflow with attacker-controlled data. Successful exploitation may allow an attacker to execute arbitrary code or crash the application, resulting in a denial of service (DoS).

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

## Which versions are affected by CVE-2026-124747?


## How do I fix CVE-2026-124747?

No fix has been published for CVE-2026-124747 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-124747 being exploited?

There is no known exploitation of CVE-2026-124747 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-124747 and fix it if it is affected.

What it is: CVE-2026-124747 is a high-severity vulnerability in Red Hat Enterprise Linux 6, published on 10 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-124747 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 6. 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-2026-124747/ (Markdown: https://insights.sbomify.com/CVE-2026-124747/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-124747
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-124747
- OSV: https://osv.dev/vulnerability/CVE-2026-124747

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-124747/
Summaries are generated and may contain mistakes; the official description above is the record.