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archive/Patch now/AIR-2025-0436
closedclosed 2 Jul 2025Patch now2 Disclosed vulnerabilityAI

CVE-2025-34072: Data exfiltration vulnerability in Anthropic Slack MCP Server

Slack Model Context Protocol Server

A data exfiltration vulnerability affects Anthropic's deprecated Slack Model Context Protocol Server through automatic link unfurling. Manipulated AI agent messages can cause zero-click data exfiltration via external preview requests.

disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why

CVSS
9.3
EPSS
<0.01 · top 63% · 2026-11-13
EPSS scores by FIRST
fix status
Fix status unknown
first report
2 Jul 2025
last update
2 Jul 2025
CVE ids
CVE-2025-34072other records

Timeline · 1

  1. 2 Jul 2025CVE-2025-34072: A data exfiltration vulnerability exists in Anthropic’s deprecated Slack Model Context Protocol (MCP) Server via automatic link…

Sources · 1

Advisories and databases

  1. 2025-07-02
    CVE-2025-34072: A data exfiltration vulnerability exists in Anthropic’s deprecated Slack Model Context Protocol (MCP) Server via automatic link…
    NVD · nvd.nist.gov/vuln/detail/CVE-2025-34072

Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.

Classification

lane
Patch now
AI role
Attack on AI
categories
Infrastructure vulnerabilityAgent hijack
severity
2 · Disclosed vulnerability
fix status
Fix status unknown
targets
Anthropic, Framework / tooling
owasp llm top 10
LLM03:2025 Supply ChainLLM06:2025 Excessive Agency
mitre atlas
AML.T0053 AI Agent Tool Invocation
tags
data-exfiltrationmcp
dates
happened 2 Jul 2025 · first reported 2 Jul 2025
origin
NVD
Vulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
record
confidence 0.95 · created 2026-10-18 10:04Z · updated 2026-10-18 10:04Z

Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned

Copy a brief

This record as a short Markdown brief, for a ticket, a chat or a coding agent.

the brief as text
# CVE-2025-34072: Data exfiltration vulnerability in Anthropic Slack MCP Server

https://gcdradar.vercel.app/incidents/cve-2025-34072-data-exfiltration-vulnerability-in-anthropic · AIR-2025-0436 · closed 2025-07-02

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2025-07-02
- AI role: Attack on AI
- Products: Slack Model Context Protocol Server
- CVE ids: CVE-2025-34072
- CVSS: 9.3

## Summary

A data exfiltration vulnerability affects Anthropic's deprecated Slack Model Context Protocol Server through automatic link unfurling. Manipulated AI agent messages can cause zero-click data exfiltration via external preview requests.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2025-07-02: CVE-2025-34072: A data exfiltration vulnerability exists in Anthropic’s deprecated Slack Model Context Protocol (MCP) Server via automatic link… (https://nvd.nist.gov/vuln/detail/CVE-2025-34072)

## Sources

- 2025-07-02 NVD: CVE-2025-34072: A data exfiltration vulnerability exists in Anthropic’s deprecated Slack Model Context Protocol (MCP) Server via automatic link… https://nvd.nist.gov/vuln/detail/CVE-2025-34072

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.

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