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    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2025-34072",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2025-04-15T19:15:22.550Z",
        "datePublished": "2025-07-02T13:46:31.554Z",
        "dateUpdated": "2025-07-02T20:29:17.261Z"
    },
    "containers": {
        "cna": {
            "affected": [
                {
                    "defaultStatus": "unaffected",
                    "modules": [
                        "Anthropic Slack MCP Server",
                        "Message content (post/reply body)"
                    ],
                    "product": "Slack MCP Server",
                    "vendor": "Anthropic",
                    "versions": [
                        {
                            "status": "affected",
                            "version": "0"
                        }
                    ]
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            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "wunderwuzzi of Embrace The Red"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "supportingMedia": [
                        {
                            "base64": false,
                            "type": "text/html",
                            "value": "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., <code>Slack-LinkExpanding</code>, <code>Slackbot</code>, <code>Slack-ImgProxy</code>) will then issue outbound requests to the attacker-controlled URL, resulting in zero-click exfiltration of private data."
                        }
                    ],
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                }
            ],
            "impacts": [
                {
                    "capecId": "CAPEC-34",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "CAPEC-34 HTTP Response Splitting"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "attackVector": "NETWORK",
                        "baseScore": 9.3,
                        "baseSeverity": "CRITICAL",
                        "privilegesRequired": "NONE",
                        "providerUrgency": "NOT_DEFINED",
                        "subAvailabilityImpact": "HIGH",
                        "subConfidentialityImpact": "HIGH",
                        "subIntegrityImpact": "HIGH",
                        "userInteraction": "NONE",
                        "valueDensity": "NOT_DEFINED",
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H",
                        "version": "4.0",
                        "vulnAvailabilityImpact": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "NONE",
                        "vulnerabilityResponseEffort": "NOT_DEFINED"
                    },
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ]
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            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-200",
                            "description": "CWE-200 Exposure of Sensitive Information to an Unauthorized Actor",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-20",
                            "description": "CWE-20 Improper Input Validation",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
                "shortName": "VulnCheck",
                "dateUpdated": "2025-07-02T13:46:31.554Z"
            },
            "references": [
                {
                    "tags": [
                        "third-party-advisory",
                        "technical-description",
                        "exploit"
                    ],
                    "url": "https://embracethered.com/blog/posts/2025/security-advisory-anthropic-slack-mcp-server-data-leakage/"
                },
                {
                    "tags": [
                        "third-party-advisory"
                    ],
                    "url": "https://vulncheck.com/advisories/anthropic-slack-mcp-server-data-exfiltration"
                }
            ],
            "source": {
                "discovery": "UNKNOWN"
            },
            "title": "Anthropic Slack MCP Server Data Exfiltration via Link Unfurling",
            "x_generator": {
                "engine": "Vulnogram 0.2.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2025-07-02T20:29:08.961760Z",
                                "id": "CVE-2025-34072",
                                "options": [
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                                        "Exploitation": "poc"
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                                    {
                                        "Automatable": "no"
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                                        "Technical Impact": "partial"
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                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
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                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-07-02T20:29:17.261Z"
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}