How severe is CVE-2025-34072?

CVE-2025-34072 has a CVSS 4.0 base score of 9.3, rated critical severity.

Is CVE-2025-34072 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2025-34072?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-34072 have an EU (EUVD) identifier?

Yes. CVE-2025-34072 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19718.

When was CVE-2025-34072 published?

CVE-2025-34072 was published on 2025-07-02 and last updated on 2026-06-17.

CVE-2025-34072

CVE-2025-34072 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 4.0 base score 9.3)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-19718
Weakness: CWE-20
Published: 2025-07-02
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2025-34072?: 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.
How severe is CVE-2025-34072?: CVE-2025-34072 has a CVSS 4.0 base score of 9.3, rated critical severity.
Is CVE-2025-34072 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-34072?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-34072 have an EU (EUVD) identifier?: Yes. CVE-2025-34072 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19718.
When was CVE-2025-34072 published?: CVE-2025-34072 was published on 2025-07-02 and last updated on 2026-06-17.

References

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