SB2026021067 - Information disclosure in Microsoft Windows NTLM
Published: February 10, 2026 Updated: February 19, 2026
Security Bulletin ID
SB2026021067
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) External Control of File Name or Path (CVE-ID: CVE-2026-21249)
CWE-ID: CWE-73 - External Control of File Name or Path
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to read arbitrary files.
The vulnerability exists due to External Control of File Name or Path in Windows NTLM. A remote attacker can trick a victim to open a specially crafted Office file and read arbitrary files on the system.
Remediation
Install update from vendor's website.