Last seen August 25, 2026

Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit

Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit The Hacker News

Technical Severity
Low severity
Lifecycle Status

STABLE

Sources

What Happened

Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit The Hacker News

Why This Matters

Publisher reporting describes a security event affecting aug. BugSkan could not yet bind a CVE or affected version, so treat the source details as the current record.

Recommended Action

Confirm whether CVE is present in your environment, compare your versions against the report, and apply available vendor patches or mitigations.

Exposure

My Interests Exposure

Exposure unknown

Recommended Response
Last Seen

Aug 25, 2026 18:13

Exposure reason: This incident does not currently match a technology in My Interests.

Exploitation status: ACTIVELY_EXPLOITED

Primary entities:

GoogleMicrosoftLLM AgentMarimoMicrosoft CopilotAI Agents

Authoritative Intelligence

CVE CVE-2026-39987 Incident identifier

EPSS is a vulnerability exploitation probability signal, not proof that your environment is exposed. CISA KEV means known exploitation of the vulnerability, not that your system was exploited.

Public GitHub References

Search GitHub for public repositories that mention this CVE. BugSkan only lists repository metadata as a defensive awareness signal — it does not fetch or display exploit code.

CVE-2026-39987 on GitHub

Timeline

  • Incident first seen
    May 29, 2026 12:30

    BugSkan first recorded this incident.

  • Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit - The Hacker News
    May 29, 2026 12:30

    news.google.com · Vulnerability

  • Marimo Notebook Flaw Could Run MCP Commands Before Cells Execute in Edit Mode
    Aug 25, 2026 18:13

    thehackernews.com · Vulnerability

  • Latest observed development
    Aug 25, 2026 18:13

    Most recent source or update associated with this incident.

Sources

Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit - The Hacker News

news.google.com · May 29, 2026 12:30

Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit The Hacker News

Open publisher source
Marimo Notebook Flaw Could Run MCP Commands Before Cells Execute in Edit Mode

thehackernews.com · Aug 25, 2026 18:13

Marimo has addressed a high-severity security flaw in its notebook software that allowed an attacker to execute an attacker-supplied Model Context Protocol (MCP) command in a specially crafted notebook, according to VulnCheck's CVE Numbering Authority (CNA) record. The CNA record says the command can run as a local subprocess when the notebook is opened in edit mode. The vulnerability, tracked

Open publisher source

My Interests Match

Want personalized relevance?

Create an account to see which incidents overlap with your interests.

← Back to incident intelligence