# CVE-2025-70616: Memory corruption in n/a

> Local attackers can exploit a stack buffer overflow in the wnBios64.sys kernel driver to achieve kernel code execution and privilege escalation.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 5 Mar 2026
- **Updated:** 6 Mar 2026
- **Also known as:** GHSA-wcpg-p923-mr58

## What is CVE-2025-70616?

CVE-2025-70616 is a high-severity memory corruption vulnerability in n/a, published on 5 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A stack buffer overflow vulnerability exists in the Wincor Nixdorf wnBios64.sys kernel driver (version 1.2.0.0) in the IOCTL handler for code 0x80102058. The vulnerability is caused by missing bounds checking on the user-controlled Options parameter before copying data into a 40-byte stack buffer (Src[40]) using memmove. An attacker with local access can exploit this vulnerability by sending a crafted IOCTL request with Options > 40, causing a stack buffer overflow that may lead to kernel code execution, local privilege escalation, or denial of service (system crash). Additionally, the same IOCTL handler can leak kernel addresses and other sensitive stack data when reading beyond the buffer boundaries.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2025-70616?

It affects 1 product.


Products: Dieboldnixdorf Wnbios64.sys.

## How do I fix CVE-2025-70616?

No fix has been published for CVE-2025-70616 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-70616 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-70616 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-70616 and fix it if it is affected.

What it is: CVE-2025-70616 is a high-severity memory corruption vulnerability in n/a, published on 5 Mar 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-2025-70616 exists.

Affected product: n/a. 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-2025-70616/ (Markdown: https://insights.sbomify.com/CVE-2025-70616/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-70616
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-70616
- OSV: https://osv.dev/vulnerability/CVE-2025-70616

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-70616/
Summaries are generated and may contain mistakes; the official description above is the record.