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Search: “Microsoft 365 Copilot”

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Microsoft Investigating Microsoft 365 Copilot Access Issues Under Incident CP1470554

Microsoft is investigating a Microsoft 365 Copilot access disruption tracked as incident CP1470554, with no root cause or recovery timeline published.

Microsoft is investigating reports that users cannot open Microsoft 365 Copilot or encounter errors when interacting with it, tracked under Service Health incident CP1470554 in the Microsoft 365 admin center. The company has not disclosed a root cause, affected regions, or estimated recovery time. It follows several distinct Copilot availability failures between late August and September 10, including an authentication-configuration outage and a Copilot Chat configuration fault. Microsoft says the issue is not a breach or cyberattack and directs tenant admins to the Service Health Dashboard.

Cyber Security Newsupdated · 16h agofirst · 5d agoAI industry 2 sources1

Microsoft Copilot Personal Flaws Could Let One Click Exfiltrate Data From Connected Apps

Varonis discloses CoSnitch (CVE-2026-24301), three Microsoft Copilot Personal flaws enabling one-click exfiltration of connected-app data; patched August 18, 2026.

Varonis Threat Labs found that an undocumented autorun=1 parameter, paired with the q parameter, lets an attacker-supplied prompt run automatically on page load in a victim's authenticated Copilot session, then exfiltrate data from connected services such as mail, calendar, Google Drive, chat history and the memory store via Copilot's built-in URL fetch to an attacker webhook. A separate memory-poisoning path through web summarization lets a crafted page persist attacker instructions in the user's memory, surviving password changes, session revocation and device re-enrollment. Microsoft shipped patches on August 18, 2026, tracked as CVE-2026-24301, and Varonis found no evidence of in-the-wild exploitation. The flaws were found via 'meta-hacking', asking Copilot itself to reveal the autorun parameter and its protections.

The Hacker News · 29d agoAI safety & securityCVE-2026-24301CVE-2026-242991

Update your firewall rules: Teams and Copilot are changing address

Microsoft is redirecting Microsoft 365 and Teams web users to new *.cloud.microsoft domains, requiring firewall and proxy rule updates by early October.

Starting September 2026, Microsoft is redirecting M365 web users to copilot.cloud.microsoft and Teams web users to teams.cloud.microsoft, announced via MessageCenter posts MC1465764 and MC1462915. All redirects should complete by early October 2026, with limited Teams exceptions possible until December 31, 2026. Microsoft advises reviewing client, proxy, firewall, and secure web gateway configurations, and suggests using TenantRestrictions to control personal Microsoft account access instead of blocking the new Copilot address.

CSO Online · 5d agoAdvisory

Most Organizations Skip Permissions Reviews Before Deploying AI Tools

Syskit survey of 327 US/UK IT leaders finds 76% deployed M365 AI tools but only 43% reviewed permissions and oversharing risk first.

Syskit's State of Microsoft 365 Governance Report 2026, based on a survey of 327 IT and security decision-makers at US and UK organizations with 500+ employees, shows most enterprises deploy AI tools like Copilot without thorough permissions reviews. Only 22% have a formal policy defining what AI agents may access, and 9% let agents inherit the deployer's full permissions. 90% report experiencing or suspecting a security incident tied to M365 misconfigurations or over-permissioned access in the past two years.

Infosecurity Magazine · 5d agoAI safety & security2· 1 read

Proofpoint Expands AI-Powered Investigations to Microsoft 365 and Deepens Insider Risk Visibility into AI Activity

Proofpoint expands AI-powered investigations into Microsoft 365 and adds AI interaction visibility to insider risk investigations.

Proofpoint announced that Prism Investigator will connect directly to Microsoft 365 email, Teams, and files without requiring archived content, expected in Q4 2026. Human Communications Intelligence agents will incorporate AI communications governance signals, capturing interactions with copilots and AI agents, into Insider Threat Management. The vendor positions these as part of a unified platform for data security, insider risk, and communications governance.

Proofpoint Threat Insight · 6d agoIndustry1

Microsoft Offers $60,000 Bounty for Critical Cross-Tenant Vulnerabilities

Microsoft expands Dynamics 365 and Power Platform bug bounty, paying up to $60,000 for critical cross-tenant vulnerabilities.

Microsoft expanded its bounty incentives for Dynamics 365 and Power Platform, with qualifying rewards from $1,250 to $60,000. Critical cross-tenant vulnerabilities receive a 100% award multiplier and important ones 50%, while critical AI inference manipulation or inferential disclosure can earn up to $30,000. Scope covers Dynamics 365 apps, Power Apps, Power Automate, Copilot Studio, Power Pages, Dataverse, and selected on-premises products. Reports must be rated Critical or Important and submitted via the MSRC Researcher Portal.

GBHackers · 1d agoIndustry

Microsoft Offers Up to $30,000 for Critical AI Flaws in Dynamics 365 and Power Platform

Microsoft expands AI bug bounty to Dynamics 365 and Power Platform, paying up to $30,000 for critical inference manipulation flaws.

Microsoft's bug bounty program offers up to $30,000 for critical 'Inference Manipulation' or 'Inferential Information Disclosure' bugs in Dynamics 365 and Power Platform, including Copilot Studio, AI Builder, Power Apps, Power Automate, and Dataverse. Payouts scale by report quality ($30,000/$20,000/$12,000 for critical) with important-severity AI flaws earning $6,000-$20,000, plus 20% multipliers for Dataverse privilege escalation and Plugin Sandbox escapes. Prompt injection affecting only the attacker, hallucinated execution, and system-prompt disclosure are excluded from scope.

Cyber Security News · 2d agoIndustry

Phishing 3.0: The Fight Moves to Agent Versus Agent

Agentic AI transforms phishing economics, enabling personalized multi-channel attacks with deepfakes like the $25M Arup deepfake heist.

The article argues phishing has evolved through three stages: from malicious content, to intent-based BEC, to AI-powered multi-channel campaigns where attacker agents autonomously conduct reconnaissance and generate tailored lures. The widely reported Arup case saw a deepfake video call impersonating colleagues convince an employee to approve transfers worth roughly $25 million. An Osterman Research study of 128 security leaders found 88% experienced trust-undermining incidents, while Microsoft 365 EOP and Google Workspace were measured missing hundreds of phishing messages per 100 mailboxes monthly. The author argues defenders must adopt their own agents to match attacker speed.

The Hacker News · 28d agoPhishing & fraud2