CVE-2025-5555: Nixdorf Wincor PORT IO Driver · Stack-based Buffer Overflow
Affects Nixdorf Wincor PORT IO DriverSource CVE Database V5
Not known to be exploited · CVSS 8.5 High.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 18 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Nixdorf Wincor PORT IO Driver | Affected
| Fixed in– |
AI-suggested
1. Immediately upgrade the Nixdorf Wincor PORT IO Driver to version 3.0.0.1 or later, as this version contains the patch addressing the buffer overflow vulnerability. 2. Restrict local access to systems running the affected driver by enforcing strict physical security controls and limiting user permissions to trusted personnel only. 3. Implement application whitelisting and endpoint protection solutions that can detect and block attempts to exploit local vulnerabilities. 4. Conduct regular audits of installed drivers and software versions on critical systems to ensure no outdated or vulnerable components remain. 5. Employ system hardening practices, including disabling unnecessary IOCTL interfaces if possible, to reduce the attack surface. 6. Monitor system logs and security alerts for unusual local activity that could indicate exploitation attempts. 7. Educate staff about the risks of local access exploitation and enforce policies to prevent unauthorized device or software installation. 8. In environments where patching is delayed, consider isolating affected systems or restricting access through network segmentation and access controls to minimize exposure.
Description
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.