11/01/2026
ISHSTB – Weekly Tech Brief | Week of Nov 1–8, 2026
Main Topic: PHP2Shell, Critical Open-Source Vulnerabilities, and the Importance of Patch Management
This week reinforces an important cybersecurity lesson: organizations don't have to run vulnerable applications directly to be affected by vulnerabilities in the technologies they depend on.
Three developments deserve attention: actively exploited PHP vulnerabilities, a serious flaw in Google's Brotli compression library, and compromised certificate authority keys. The common theme? Visibility, patch management, and knowing what's running across your environment.
1. PHP2Shell: Critical PHP vulnerabilities actively exploited
Two critical remote code ex*****on vulnerabilities (CVE-2026-109618 and CVE-2026-109619) were disclosed in PHP. Both were added to CISA's Known Exploited Vulnerabilities (KEV) catalog on October 26.
- Fixed releases: PHP 8.5.12, 8.4.27, 8.3.36 and 8.2.35.
- Organizations should identify exposed PHP installations, including older website platforms, hosting environments and custom applications.
- Patching alone isn't enough: investigate whether vulnerable systems were previously compromised.
MSSP Action: Help clients identify vulnerable assets, prioritize emergency patching, verify remediation and investigate suspicious activity.
Microsoft+1
2. Brotli vulnerability: Beyond PHP
A serious vulnerability in Google's Brotli compression library (CVE-2026-111497) affects multiple technologies, including Node.js, .NET, PowerShell 7, Visual Studio and PHP.
The vulnerability was also added to CISA's KEV catalog. Microsoft released out-of-band security updates, making this a reminder that dependencies can introduce risk across otherwise trusted environments.
MSSP Action: Review software inventories, update affected runtimes and applications, and verify that out-of-band updates and required restarts are completed.
Microsoft
3. Microsoft 365: MFA isn't the whole story
A token-replay campaign compromised 97 Microsoft 365 accounts across 79 organizations. Attackers used adversary-in-the-middle phishing to capture authentication sessions and replay stolen tokens.
The campaign also involved rogue Entra devices, unauthorized MFA registrations and hidden mailbox rules.
MSSP Action: Help clients strengthen Conditional Access, review Entra device registrations, monitor MFA changes, investigate suspicious inbox rules and revoke compromised sessions.
The Hacker News
Bottom Line
Security isn't simply about having MFA enabled or installing monthly patches. Organizations need continuous visibility into identities, applications, dependencies and infrastructure.
This week's developments are another reminder that attackers look for the gaps between security controls.