Week 7 – Microsoft Patch Tuesday
9 – 15 Feb 2026
In this week’s CVE of the Week, we’ll be looking at one of the vulnerabilities updated during Microsoft’s February 2026 Patch Tuesday.
CVE-2026-21510 is a protection mechanism failure that could allow an unauthorized attacker to bypass a security feature affecting Windows Shell. The vulnerability was assigned a CVSSv3 score of 8.8 and was rated as important.
According to Microsoft, an attacker could bypass Windows SmartScreen and Windows Shell security prompts by exploiting improper handling in Windows Shell components, allowing attacker-controlled content to execute without user warning or consent. Exploitation requires an attacker to convince an user to open a malicious link or shortcut file.
The flaw was publicly disclosed prior to a patch being made available and was subsequently exploited in the wild as a zero-day.
The following security updates and hardening configurations are recommended to remediate this vulnerability:
- Install the latest security updates for Windows
- Review and harden Windows Shell configurations
- Monitor for suspicious network activity
Microsoft has attributed the discovery of the flaw to Microsoft Threat Intelligence Center (MSTIC), Microsoft Security Response Center (MSRC), Office Product Group Security Team, Google Threat Intelligence Group, and an anonymous researcher.
Microsoft also released patches for 59 vulnerabilities affecting its software ecosystem, including five more that have been confirmed as exploited in the wild. The severity breakdown includes five Critical, 52 Important, and two Moderate vulnerabilities.
For additional information about the referenced CVE and the Patch Tuesday updates, please visit:
Microsoft advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21510
CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-21510
February 2026 Patch Tuesday: https://thehackernews.com/2026/02/microsoft-patches-59-vulnerabilities.html
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