Critical Security Update: December 19, 2025 (Microsoft, Cisco, WatchGuard, WhatsApp, Microsoft 365)
Critical Security Update
Microsoft, Cisco, WatchGuard, WhatsApp, Microsoft 365
Risk 1: Low
Issue: A growing concern recently with the usage of WhatsApp is hackers taking advantage of the ease to add additional devices. Once a malicious actor links to. your account and adds it to their (typically virtual) device, they have ongoing 24/7 access to your account.
Resolution: WhatsApp users should ensure they have multifactor authentication enabled and that they are regularly checking the devices connected to their account. Due to the ease of this access, accounts should be checked regularly.
Due to the recent and ongoing concerns connected to WhatsApp, we are downgrading the overall security value linked to WhatsApp. Users should increase ongoing caution when using this app.
Risk 2: High
Issue: Microsoft 365 credentials currently have a raised risk factor through third-party authentication sites using technology known as 0Auth. 0Auth is the technology enabling “Login With Your Microsoft/Facebook/Google/Etc Account”. There has been nearly triple the number of phishing attacks going after Microsoft 365 0Auth accounts.
Resolution: Users should exercise added caution when logging in to accounts using these shared credentials. Similarly, and I sound like a broken record, ensure MFA is enabled on all your shared credential accounts.
Additionally, since the heightened risk is currently connected to phishing attacks, users should go directly to the website they wish to use instead of click a link or redirecting from an e-mail.
Risk 3: Medium
Issue: WatchGuard, a maker of enterprise firewalls, has recently announced a sever vulnerability currently being exploited across their collection of devices. This vulnerability allows full remote access and control over the network behind the firewall. This is a pretty severe vulnerability.
Resolution: WatchGuard has deployed a patch and all WatchGuard users should immediately download and apply the patch/update.
Risk 4: Medium
Issue: A recent vulnerability connected to Cisco VPNs has been located in connection to password spraying attempts. Password spraying is when a large number of passwords are tried against an account, or collection of accounts, trying to find a matching combination. Cisco VPN products are currently under heightened attack.
Resolution: Any Cisco VPN user should ensure they are regularly changing their passwords and using a complicated series of characters. If your version of Cisco VPN permits locking or timing out an account after X failed attempts, you should immediately enable that feature.
Risk 5: Low
Issue: Microsoft has announced that it will begin limiting access to its online services. This first limitation will be users using Exchange Online beginning March 1, 2026. The first push will block access to devices under an iPhone 10. For Android users, Google is currently working with Microsoft to rollback changes to older versions. No details are currently available.
Resolution: For users on Microsoft Online services, they should ensure they are using a modern iPhone to maintain connectivity. Android users will need to verify closer to the cut-off date, but users with devices less than 8 years old can expect to be fine.
Announced Data Breaches
Denmark
France
Coupang
University of Sydney
PDVSA
SoundCloud
PornHub
700Credit
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