ZeroHour
Schneier on Securitypublished ()ingested Bruce Schneier

Twelve-Year-Old Vulnerability Found in Windows Defender

mediumVulnerabilityimportance 30
Full article175 words · extracted from schneier.com · click to collapse

Researchers found, and Microsoft has patched, a vulnerability in Windows Defender that has been around for twelve years. There is no evidence that anyone has used the vulnerability during that time.

The flaw, discovered by researchers at the security firm SentinelOne, showed up in a driver that Windows Defender—renamed Microsoft Defender last year—uses to delete the invasive files and infrastructure that malware can create. When the driver removes a malicious file, it replaces it with a new, benign one as a sort of placeholder during remediation. But the researchers discovered that the system doesn’t specifically verify that new file. As a result, an attacker could insert strategic system links that direct the driver to overwrite the wrong file or even run malicious code.

It isn’t unusual that vulnerabilities lie around for this long. They can’t be fixed until someone finds them, and people aren’t always looking.

Tags: malware, Microsoft, patching, vulnerabilities, Windows

Posted on February 24, 2021 at 6:19 AM33 Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.

Text extracted automatically; images, tables and formatting may be missing. Original: https://www.schneier.com/blog/archives/2021/02/twelve-year-old-vulnerability-found-in-windows-defender.html