Microsoft Patch Tuesday (October 2026)

Microsoft has published its October 2026 security updates, addressing 1,453 CVEs across 227 distinct updates. Among them, a Windows Shell security-feature bypass (CVE-2026-96951) shows signs of active exploitation, and a .NET Framework security-feature bypass (CVE-2026-108398) was publicly disclosed. Apply the October cumulative updates, prioritizing Windows Shell and .NET exposure on internet-facing systems.

Source: https://msrc.microsoft.com/update-guide/releaseNote/2026-Oct

Linux kernel: seven stable releases, critical network fix

The Linux kernel maintainers shipped seven new stable kernels (7.2.11, 6.18.57, 6.12.113, 6.6.159, 6.1.190, 5.15.223, 5.10.272), including a fix for a critical network-stack flaw that could corrupt packet headers when processing IPv4 traffic with bad checksum metadata. The issue can lead to memory corruption and denial of service, so the fixes matter for anything exposed on the network. A normal system update covers these branches.

Source: https://lwn.net/Articles/1100611/

CISA adds an Atlassian flaw to its Known Exploited Vulnerabilities catalog

CISA listed CVE-2026-21589, a "Files or Directories Accessible to External Parties" vulnerability affecting multiple Atlassian products, based on evidence of active exploitation. It raises the urgency for any exposed Jira, Confluence, or other Atlassian instance that reads publicly reachable file or directory paths. Patch to a current release and harden external access to Atlassian apps.

Source: https://www.cisa.gov/news-events/alerts/2026-10-15/cisa-adds-one-known-exploited-vulnerability-catalog

Mobile apps are quietly becoming business endpoints

A new Cyber Safety newsletter notes that, as corporate work migrates to phones, apps with broad, easily-granted permissions (contacts, location, files) can quietly expose company data, especially under bring-your-own-device setups. It recommends extending endpoint controls to phones: enforce encryption and strong screen locks, keep the OS updated, and restrict risky permissions. Reconcile app permissions and MDM policy on the devices staff use for work.

Source: https://newsletter.cyber-safety.co/p/your-mobile-apps-could-be-exposing-company-data