Buffer overflow in Nixdorf Wincor Port Io Driver
CVE-2025-5555
A vulnerability has been found in Nixdorf Wincor PORT IO Driver up to 1.0.0.1. This affects the function sub_11100 in the library wnport.sys of the component IOCTL Handler. Such manipulation leads to stack-based buffer overflow. Local access is required to approach this attack. The exploit has been disclosed to the public and may be used. Upgrading to version 3.0.0.1 is able to mitigate this issue. Upgrading the affected component is recommended. The vendor was contacted beforehand and was able to provide a patch very early.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (12.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 13th percentile — 12.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Nixdorf Wincor Port Io Driver — versions 1.0.0.0, 1.0.0.1, 3.0.0.1
Weakness classification (CWE)
References
- vuldb.com/ (technical-description, vdb-entry)
- vuldb.com/ (signature, permissions-required)
- vuldb.com/ (third-party-advisory)
- b.iakb.org/2025/06/26/Wincor-Nixdorf-PORT-IO-Driver-Buffer-Overflow/ (exploit, broken-link)
- download.dieboldnixdorf.com/ (patch)
Frequently asked questions
- What is CVE-2025-5555?
- CVE-2025-5555 is a high-severity vulnerability in Nixdorf Wincor Port Io Driver, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2025-10-18.
- How severe is CVE-2025-5555?
- High severity. CVSS v3 base score is 7.8 out of 10.