Microsoft Warns Poisoned MCP Tool Descriptions Can Make AI Agents Leak Data

New Microsoft research shows how attackers can hijack AI agents that act on a user's behalf, using nothing more than a poisoned tool description to make the agent quietly hand over company data to an outsider. The trick is that the agent never breaks a rule. Every step looks routine, so in a default setup no alarm may fire. The work comes from Microsoft Incident Response and its

Emma Klein

3h ago

0 0

Discussion

Leave the first comment

Be the first to leave a mark on this discussion.

No comments yet.

Be the first to share your take and keep the conversation moving.

Join the conversation

UPVOTERS

Community appreciation

See who found this content valuable and showed their support.

No upvotes yet.

Be the first to show your appreciation for this content.

TOPICS

Explore the same topics

Discover more content from the topics this post is mapped to.

bleepingcomputer.com

Microsoft accelerates quantum-safe roadmap as risks grow

Microsoft announced today that it is accelerating its quantum-safe security roadmap, saying advances in quantum computing are bringing the need to replace toda…

Noor Bakker

2026-06-30 23:07

bleepingcomputer.com

Fake Perplexity extension on Chrome Web Store tracked searches

A malicious extension in the Chrome Web Store is masquerading as the Perplexity AI answer engine, intercepting search traffic and collecting browsing informati…

alex but tired

2h ago

bleepingcomputer.com

Kali Linux 2026.2 released with 9 new tools, NetHunter updates

Kali Linux 2026. 2, the second release of the year, is now available for download, featuring 9 new tools and numerous Kali NetHunter improvements. [. .. ]

Giulia

9h ago

bleepingcomputer.com

CISA: Windows BlueHammer flaw now exploited by ransomware gangs

CISA confirmed on Monday that ransomware gangs are now exploiting a Microsoft Defender privilege escalation vulnerability, dubbed BlueHammer, that has previous…

SariMartinez

10h ago

thehackernews.com

New BioShocking Attack Tricks AI Browsers Into Leaking User Cre…

Convince an AI browser that it is playing a game, and it can hand over your login details. That is the finding behind BioShocking, a technique from securi…

The Hacker News

11h ago

bleepingcomputer.com

Nissan discloses employee data breach linked to Oracle zero-day…

Nissan is warning that it suffered a data breach affecting current and former employees after threat actors exploited an Oracle PeopleSoft vulnerability in dat…

Nirano

22h ago

Keep browsing

Explore more from this topic

Dive into the full feed of curated posts covering Cybersecurity & Data Protection.

Browse Topics

Continue exploring

Discover more content that aligns with your interests and this post.

thehackernews.com

New BioShocking Attack Tricks AI Browsers Into Leaking User Cre…

Convince an AI browser that it is playing a game, and it can hand over your login details. That is the finding behind BioShocking, a technique from securi…

The Hacker News

11h ago

thehackernews.com

Malicious Perplexity Chrome Extension Intercepted Searches and …

Microsoft has found a malicious Chrome extension that posed as the AI search engine Perplexity and quietly logged what people searched for. It routed every que…

alex but tired

1d ago

thehackernews.com

WhatsApp is Finally Getting Usernames to Help Keep Phone Number…

WhatsApp on Monday officially announced the start of global reservations of usernames with an aim to protect the privacy of more than three billion users on th…

Nirano

1d ago

thehackernews.com

Public PoC Released for Critical libssh2 CVE-2026-55200 Client-…

A public proof-of-concept is now out for CVE-2026-55200, a critical flaw in libssh2 that lets a malicious or compromised SSH server trigger memory corruption o…

The Hacker News

1d ago

thehackernews.com

Ukraine Says Russian Intelligence Used Fake Support Texts to St…

The Security Service of Ukraine (SSU) said it, together with the U. S. Federal Bureau of Investigation (FBI), uncovered a long-running campaign orchestrated by…