Search criteria
2 vulnerabilities found for Slack MCP Server by Anthropic
CVE-2025-34072 (GCVE-0-2025-34072)
Vulnerability from cvelistv5 – Published: 2025-07-02 13:46 – Updated: 2025-07-02 20:29
VLAI?
Title
Anthropic Slack MCP Server Data Exfiltration via Link Unfurling
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.
Severity ?
CWE
Assigner
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
|
||||||||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Anthropic | Slack MCP Server |
Affected:
0
|
Credits
wunderwuzzi of Embrace The Red
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CVE-2025-34072 (GCVE-0-2025-34072)
Vulnerability from nvd – Published: 2025-07-02 13:46 – Updated: 2025-07-02 20:29
VLAI?
Title
Anthropic Slack MCP Server Data Exfiltration via Link Unfurling
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.
Severity ?
CWE
Assigner
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
|
||||||||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Anthropic | Slack MCP Server |
Affected:
0
|
Credits
wunderwuzzi of Embrace The Red
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