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🔒 The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added three Linux kernel vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog after evidence of active exploitation. The flaws include high-severity issues in the TLS receive path, ebtables SNAT ARP rewrite, and an AF_ALG socket race condition, with CVSS scores of 9.8, 8.8, and 7.8 respectively. Red Hat updated advisories on September 19, 2026, urging immediate remediation, and FCEB agencies are recommended to patch by September 21, 2026 under BOD 26-04.

🔒 AWS Continuum for penetration testing introduces a frontier agent that performs on-demand, customized penetration tests with real exploitability checks. The new capability authenticates using provided login credentials before a full test, capturing and suggesting all accessible domains reached during login to help define accurate network scope. Accessible domains are surfaced whether credential attempts succeed, fail, or time out, reducing misconfiguration and wasted test cycles.

🛡️ A researcher published working exploits for four Linux kernel local privilege-escalation flaws called DirtyAH6, TUNderflow, PPPoEject, and DiagSpill. Kernel maintainers have released fixes in recent stable kernels, so up-to-date systems are not vulnerable, but unpatched machines should be updated promptly. Three flaws require unprivileged user namespaces to reach, while DiagSpill needs only SCTP support. The exploits are tuned to specific builds, may crash systems, and so far show no evidence of in-the-wild use.

🐧 Amazon Elastic Container Service Express Mode now supports specifying ARM64 as the CPU architecture for services, enabling deployment of ARM-based container images on AWS Graviton-powered compute with up to 40% better price-performance versus x86. ECS Express Mode orchestrates networking, load balancing, autoscaling and deployments, providing an auto-generated URL while simplifying launches of web apps and APIs. Users can set the CPU architecture for new and existing services via the AWS Console, CLI, SDKs, or IaC tools, and the feature is available in all AWS commercial Regions and AWS GovCloud (US).

🔎 This post describes how Cloudflare reduced memory usage in its Pingora Backend Router by optimizing consistent hashing. The team identified excessive memory in the pingora-ketama structures and analyzed how hash counts, weights, and collisions affect load distribution. A Rust-level storage change and mathematical analysis allowed them to safely shrink per-server hash counts and reclaim significant RAM without disrupting cache routing.

🔒 WordPress issued an urgent security patch (7.1.1) to address a vulnerability dubbed Click2Shell discovered by pwn.ai, which can cause a crafted link opened by a logged-in administrator to install an official WordPress.org theme without clicking Install. The core bug alone installs a legitimate theme, but chained with a separate theme flaw it can lead to remote code execution. Site operators should update immediately; affected branches back to 4.7 received fixes.

🔒 CISA will discontinue its weekly vulnerability bulletin effective September 28, citing the new Binding Operational Directive (BOD 26-04) that requires prioritizing patches based on real-world exploitation rather than severity scores. The agency points to rising AI-driven threats and urges CISOs to rely more on vendors' security bulletins and updates. CISA will continue other channels like KEV, Cybersecurity Alerts and CVE catalogs to share critical information.

🔧 AWS Resilience Hub introduces three capabilities: EKS labels as service input sources, generative AI-powered dependency insights, and resilience policy sharing via AWS Organizations. EKS labels let teams scope discovery using Kubernetes labeling conventions. Dependency insights analyze discovered dependencies to surface new links, cross-Region dependencies, and unusual patterns. Policy sharing enables centralized policy distribution and organization-wide observability.

📰 This post introduces native BM25 full-text search in AlloyDB and Cloud SQL for PostgreSQL 17+ via the open-source pg_textsearch extension from TigerData. The change eliminates the need for separate full-text backends, reducing data duplication and sync complexity while delivering industry-standard BM25 ranking directly in the database. AlloyDB further offers accelerated vector search (ScaNN, HNSW) and an out-of-the-box hybrid search UDF to merge vector and keyword results; Cloud SQL supports hybrid results via CTEs and coalesced RRF scoring.

🛡️ Gyazo, a cloud-based screenshot and screen-recording service, confirmed a data breach after attackers exploited a server vulnerability on September 11, 2026, stealing roughly 23.62 million user records. The company detected the activity on September 12, patched the flaw, and has taken the service offline for maintenance while investigating with external experts. Exposed data may include names, emails, password hashes, session tokens, image metadata, and more, prompting recommendations that users change reused credentials and watch for suspicious communications.

🔒 Today Google Cloud announced enhancements to the borderless Lakehouse to let data engineers, analysts, and AI agents query governed data in place across clouds. The update introduces preview cross-cloud caching for BigQuery to reduce remote data transfer by caching columnar blocks locally and preview cross-cloud connections to query non-Iceberg data. The features use the Apache Iceberg REST catalog spec, Partner Cross-Cloud Interconnect, and default encryption to improve performance, security, and TCO for multi-cloud analytics.

🔒 Google describes AI-native, agent-driven methods that embed high-precision vulnerability scanning and automated patching into the software development lifecycle. By evolving the open-source Mantis multi-agent harness and using localized threat models plus call-graph analysis, pre-submit scans detect issues in near real-time with low false-positive rates. A two-step validation (fast triage agent then nightly post-submit testing) and an automated bug-fix agent streamline detection-to-resolution while preserving developer productivity.

🔒 Researchers discovered a zero-click vulnerability called Plugin4Shell affecting AI coding agents like Codex, Claude Code, Gemini CLI, and GitHub Copilot, allowing attackers to swap trusted plugins for malicious ones and execute code without developer interaction. The flaw stems from agents passing a Git commit SHA to Git but not verifying the checked-out commit, enabling repository owners or takeovers to resolve a malicious version under the expected identifier. Some vendors have patched the issue, while others have deprecated components or applied mitigations; enterprises are urged to inspect affected machines and audit logs.

🛠️ AWS RTB Fabric now supports configurable Availability Zone affinity for responder gateways, letting partners connect either within their own AZ or to any AZ the gateway spans. This option helps AdTech companies optimize infrastructure use and avoid underutilized capacity without additional RTB Fabric charges. Configurable AZ affinity is available in all Regions where RTB Fabric is offered; check the AWS RTB Fabric User Guide for fleet requirements before enabling.

🔒 Researchers at eSentire discovered GhostCode, a phishing kit that abuses Microsoft’s OAuth 2.0 device authorization flow to trick users into granting attacker-controlled devices access to Microsoft 365 accounts. Victims are lured via procurement-themed social engineering to enter device codes on legitimate Microsoft sign-in pages, completing MFA for the attacker’s session. Stolen tokens enabled automated device registration, Intune enrollment and acquisition of Primary Refresh Tokens (PRTs), persisting access even after token revocation. eSentire recommends restricting device-code flow via Conditional Access, monitoring device registrations and Python-based user agents, and auditing Entra ID for suspicious device patterns.

🚀 Moonshot AI's Kimi K3 is now generally available on Amazon Bedrock, delivering an open-weight model with native vision and a 1-million-token context window. The model, claimed to have 2.8 trillion parameters and improved scaling efficiency over Kimi K2, targets long-running coding sessions, multi-document analysis, and extended agent workflows. On Bedrock it runs within the same security boundary as proprietary models and supports explicit prompt caching to reduce latency and input costs.

📣 Amazon Simple Notification Service (Amazon SNS) now supports message payloads up to 1 MiB, a 4x increase from the prior 256 KiB limit. This change lets you publish larger messages to both Standard and FIFO topics by configuring the new MaximumMessageSize topic attribute. Topics with sizes above 256 KiB are compatible with Amazon SQS, Amazon Data Firehose, and AWS Lambda subscriptions, supporting up to 100 subscriptions per topic. The feature is available today in all Regions where Amazon SNS operates.

🛡️ Microsoft Teams will let administrators customize the list of file extensions blocked by the built-in Weaponizable File Protection feature to align with organizational security policies. The capability is in development and slated to begin rolling out in November 2026 across Android, desktop, iOS, macOS, and web for standard multi-tenant cloud environments. Previously, admins could only rely on Microsoft’s default blocked file list. The change gives organizations greater flexibility to tailor file protection while preserving secure collaboration.