High severity · published Oct 6, 2026
CVE-2026-84854
Out of Bound Write on WibuKey for Windows
7.0
CVSS
0.1%
EPSS
No
On KEV
Description
In the WibuKey driver for Windows below Version 6.72, insufficient validation of user input when calculating the size of a kernel buffer could cause small amounts of data to be written outside the intended kernel buffer. This can lead to a system crash. Under unfavorable circumstances, adjacent kernel memory may be modified.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 1% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WI
wibukey · wibu-systems-ag
before 6.72 · source: vendor
PV
PSS(R)SINCAL V21.5 · Siemens
0 · source: CISA
PV
PSS(R)SINCAL V22.0 · Siemens
0 · source: CISA
PV
PSS(R)SINCAL V22.5 · Siemens
before V22.5 Update 5 · source: CISA
In the news
VulnerabilityHigh
Siemens PSS(R)SINCAL
View CSAF
Summary
PSS(R)SINCAL uses WibuKey third-party product that contains an out-of-bounds write vulnerability. An attacker could exploit this vulnerability to cause a system crash, resulting in a denial-of-service condition. This affects PSS SINCAL only when configured to use the legacy WibuKey dongle license type. Siemens is actively preparing updates and recommends applicable mitigations for products where patches are currently unavailable.
The following versions of Siemens PSS(R)SINCAL are affected:
PSS(R)SINCAL V21.5 vers:all/* (CVE-2026-84854)
PSS(R)SINCAL V22.0 vers:all/* (CVE-2026-84854)
PSS(R)SINCAL V22.5 vers:intdot/<22.5.5 (CVE-2026-84854)
CVSS
Vendor
Equipment
v3 7
Siemens
PSS(R)SINCAL V21.5
1 Vulnerability
Out-of-bounds Write
Background
Critical Infrastructure Sectors: Critical Manufacturing, Transportation Systems, Energy, Healthcare and Public Health, Financial Services, Government Services and Facilities
Countries/Areas Deployed: Worldwide
Company Headquarters Location: Germany
Vulnerabilities
CVE-2026-84854
In the WibuKey driver, insufficient validation of user input when calculating the size of a kernel buffer could cause small amounts of data to be written outside the intended kernel buffer. This can lead to a system crash. Under unfavorable circumstances, adjacent kernel memory may be modified.
Read More
3 Affected Products
PSS(R)S...
Oct 22, 2026·CISA Advisories
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84854
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-84854
vendor-advisory
https://cdn.wibu.com/fileadmin/wibu_downloads/security_advisories/AdvisoryWIBU-100065.pdf
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