Vulnerabilites related to Anthropic - Slack MCP Server
CVE-2025-34072 (GCVE-0-2025-34072)
Vulnerability from cvelistv5
Published
2025-07-02 13:46
Modified
2025-07-02 20:29
Severity ?
VLAI Severity ?
EPSS score ?
CWE
Summary
A data exfiltration vulnerability exists in Anthropic’s deprecated Slack Model Context Protocol (MCP) Server via automatic link unfurling. When an AI agent using the Slack MCP Server processes untrusted data, it can be manipulated to generate messages containing attacker-crafted hyperlinks embedding sensitive data. Slack’s link preview bots (e.g., Slack-LinkExpanding, Slackbot, Slack-ImgProxy) will then issue outbound requests to the attacker-controlled URL, resulting in zero-click exfiltration of private data.
References
▼ | URL | Tags |
---|---|---|
https://embracethered.com/blog/posts/2025/security-advisory-anthropic-slack-mcp-server-data-leakage/ | third-party-advisory, technical-description, exploit | |
https://vulncheck.com/advisories/anthropic-slack-mcp-server-data-exfiltration | third-party-advisory |
Impacted products
Vendor | Product | Version | ||
---|---|---|---|---|
Anthropic | Slack MCP Server |
Version: 0 |
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