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Episode #838 Quiz

Autodiscover.fiasco
Date: 2021-09-28 | Length: 1.5 hrs | Episode page at twit.tv

About this episode

Chrome’s 12th zero-day of 2021 fixed a use-after-free in the Portals API, while Apple patched actively exploited iOS/macOS flaws, including a kernel type-confusion bug and WebKit-related attacks. Guardicore showed Outlook’s Autodiscover can leak Windows credentials via HTTP fallback and domain collision, prompting Microsoft domain registration mitigations.

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Question 1: According to the episode, what was the key consequence of the malformed certificate technique used by OpenSUpdater on Windows systems?

Question 1

According to the episode, what was the key consequence of the malformed certificate technique used by OpenSUpdater on Windows systems?

Windows accepted the certificate while third-party antimalware rejected it Both Windows and third-party antimalware treated the certificate as invalid Windows rejected the certificate while third-party antimalware accepted it Both Windows and third-party antimalware treated the certificate as valid

Question 2: What was the specific protocol downgrade behavior Guardicore described in the Autodiscover research?

Question 2

What was the specific protocol downgrade behavior Guardicore described in the Autodiscover research?

A 302 redirect could force a switch from NTLM to Kerberos A timeout could force a switch from HTTPS to SMTP plaintext A DNS NXDOMAIN could force a switch from PKCE to Basic Auth A 401 response could force a switch from OAuth or NTLM to HTTP Basic Auth

Question 3: Which pair of Autodiscover-related applications did the episode say were both involved in the credential leak observed by Guardicore?

Question 3

Which pair of Autodiscover-related applications did the episode say were both involved in the credential leak observed by Guardicore?

Microsoft Outlook and mobile email clients Outlook and Exchange Server management consoles Microsoft Teams and web browsers Thunderbird and calendar sync daemons

Question 4: What limitation of Microsoft's newly updated PC Health Check Tool did Steve identify in the episode?

Question 4

What limitation of Microsoft's newly updated PC Health Check Tool did Steve identify in the episode?

It only checked storage space and ignored CPU compatibility It would not run on Windows 7 and required Windows 10 It would not run on Windows 11 and required Windows 10 It required an ARM processor and refused Intel systems

Question 5: What did Microsoft say was the remediation path for the Patch Tuesday issue affecting apps when EAF was enabled?

Question 5

What did Microsoft say was the remediation path for the Patch Tuesday issue affecting apps when EAF was enabled?

Disable Windows Defender and reinstall the affected applications Apply a registry fix from a standalone hotfix package Use the Known Issue Rollback and wait for propagation Remove EAF from Exploit Protection and reboot immediately

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