# CVE-2026-116776: USB Test: Heap-based Buffer Overflow in getSectorSize via untrusted DISK_GEOMETRY.BytesPerSector leads to RCE/DoS


- **Severity:** High 7.0 (`CVSS:4.0/AV:P/AC:L/AT:N/PR:H/UI:P/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 28 Oct 2026
- **Updated:** 29 Oct 2026
- **Also known as:** GHSA-cfrv-c9q2-7cr3

## What is CVE-2026-116776?

CVE-2026-116776 is a high-severity vulnerability in n-romanovich usb-test, published on 28 Oct 2026. 

### Official description

USB Test is a lightweight Windows CLI utility for verifying sector integrity and detecting overreported capacity on USB flash drives. Prior to version 1.1.5, getSectorSize() in USB Test/src/driveinfo.cpp trusts DISK_GEOMETRY.BytesPerSector returned by IOCTL_DISK_GET_DRIVE_GEOMETRY without checking whether the call succeeded or enforcing size bounds. USB Test/src/drivetest.cpp uses the value for division and to size a heap buffer before memcpy(buffer.data(), &sector, 8), so a physically connected malicious USB storage device can report a value below eight bytes and cause repeated out-of-bounds writes, or report zero and cause a divide-by-zero denial of service when a user starts a drive test. The heap corruption can crash the elevated application and may permit arbitrary code execution. This issue is fixed in version 1.1.5.

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-116776?


## How do I fix CVE-2026-116776?

No fix has been published for CVE-2026-116776 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-116776 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-116776 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-116776 and fix it if it is affected.

What it is: CVE-2026-116776 is a high-severity vulnerability in n-romanovich usb-test, published on 28 Oct 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-116776 exists.

Affected product: n-romanovich usb-test. 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-2026-116776/ (Markdown: https://insights.sbomify.com/CVE-2026-116776/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-116776
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-116776
- OSV: https://osv.dev/vulnerability/CVE-2026-116776

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-116776/
Summaries are generated and may contain mistakes; the official description above is the record.