CVE-2026-55580
Default-config flaw in mcp-shell allows remote execution of OS commands.
Is CVE-2026-55580 being exploited?
Not confirmed. CVE-2026-55580 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.15% probability of exploitation in the next 30 days.
How severe is CVE-2026-55580?
CVE-2026-55580 is rated High with a CVSS score of 8.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-55580?
Yes. A fix has been recorded for CVE-2026-55580. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-55580 affect?
CVE-2026-55580 affects mcp-shell < 0.6.0, Deployments using README bare-binary without MCP_SHELL_SEC_CONFIG_FILE, Hosts/containers running mcp-shell. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-55580?
Upgrade to mcp-shell 0.6.0 and set MCP_SHELL_SEC_CONFIG_FILE with a security policy.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote code execution: attacker or an LLM over stdio can execute arbitrary OS commands as the mcp-shell process user, enabling data access and further compromise.
Immediate action required
- affected< 0.6.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.