4 comments

  • egeozcan 1 hour ago
    I wonder why Windows Defender has the privilege to alter the system files. Read them for analysis? Sure! Reset (as in, call some windows API to have it replaced with the original), why not? But being able to write sounds like a bad idea.

    However, I don't know what I'm talking about so take it with a grain of salt!

    • EvanAnderson 58 minutes ago
      AV had traditionally run as SYSTEM on Windows (and, in the past, often had kernel mode drivers too). I've always thought it was a terrible idea. It opens up exciting new attack surfaces. Kaspersky and McAfee both had privilege escalation vulnerabilities that I can recall. There have been a ton in multiple products over the years.
      • labelbabyjunior 53 minutes ago
        They kind of have to, though.

        If malware exploits a privilege escalation vuln, what's the AV going to do about it when it's reduced to the software equivalent of a UK police officer? Observe and report? Stop or I'll say "stop" again?

        AV requires great power, which requires great responsibility. The second part is what often eludes AV developers.

        • EvanAnderson 45 minutes ago
          The OS should do the SYSTEM-level lifting and scanning processes and behavior analysis should run sandboxed as low priv processes. It would require a clearly defined API and I feel like MSFT was always reticent to commit, leaving AV manufacturers to create hacky nightmares.
          • labelbabyjunior 42 minutes ago
            Well the OS should do nothing—remember MS was taken to court over that—but better privsep on the part of the AV, sure.

            Technically, Defender can be replaced with 3rd party AV.

    • labelbabyjunior 57 minutes ago
      Some files under Windows are protected as the TrustedInstaller user, which is a more restrictive level of permissions than SYSTEM.
  • labelbabyjunior 1 hour ago
    A local privilege escalation to root via an exploitable service?

    Doesn't Linux have one of these CVEs...each week?

    • hsbauauvhabzb 25 minutes ago
      Probably, but is that service deployed as part of the base operating system or a third party package? Can you remove the service if you deem the crazy service behaviour is unnecessary or too risky for your usecase?
  • ranger_danger 2 hours ago
    > normally I would just drop the PoC code and let people figure it out

    Looks like that's exactly what they did though?

    Or maybe they just meant that they don't usually explain how it works?

    • kijin 1 hour ago
      Tney gave it a sexy name and set up a website about it (a github repo, at any rate), instead of just talking about it in a mailing list and getting a CVE like a proper bearded security researcher.