{"data":{"id":"8d4490e5-f779-4ea1-a7c6-813c266f2cb2","title":"GHSA-3x77-wg38-92r3: mcp-shell has a Secure Mode Allowlist Bypass via Default `/bin/bash` Executable","summary":"mcp-shell's default Docker configuration (security.yaml) includes /bin/bash in allowed_executables, and the command validator in security.go checks only the first token, so it does not block shell flags such as -c. Any MCP tool caller can send command=/bin/bash -c <arbitrary-command> to shell_exec, with no authentication or configuration changes needed, and run binaries outside the allowlist as mcpuser inside the container.","solution":"N/A -- no mitigation discussed in source.","labels":["security"],"sourceUrl":"https://github.com/advisories/GHSA-3x77-wg38-92r3","publishedAt":"2026-08-25T15:41:30.000Z","cveId":"CVE-2026-55581","cweIds":null,"cvssScore":null,"cvssSeverity":"high","severity":"high","attackType":["other"],"issueType":"vulnerability","affectedPackages":["github.com/sonirico/mcp-shell@< 0.6.0 (fixed: 0.6.0)"],"affectedPackageNames":["github.com/sonirico/mcp-shell"],"affectedPackageRefs":["go:github.com/sonirico/mcp-shell"],"affectedVendors":[],"affectedVendorsRaw":["mcp-shell"],"classifierModel":"claude-haiku-5-5","classifierPromptVersion":"v4","summaryPromptVersion":"v2","headline":null,"headlinePromptVersion":null,"cvssVector":null,"attackVector":null,"attackComplexity":null,"privilegesRequired":null,"userInteraction":null,"exploitMaturity":"unknown","epssScore":0.00454,"epssCheckedAt":"2026-11-04T12:08:34.077Z","kevDateAdded":null,"advisoryAliases":["GHSA-3x77-wg38-92r3"],"affectedPackagesSource":null,"affectedPackagesCheckedAt":null,"patchAvailable":true,"disclosureDate":"2026-08-25T15:41:30.000Z","fixReleasedAt":"2026-06-14T11:30:25.000Z","daysToFix":-72,"fixCheckedAt":"2026-10-29T21:31:15.785Z","capecIds":null,"crossRefCount":0,"attackSophistication":"trivial","impactType":["confidentiality","integrity","availability"],"aiComponentTargeted":"plugin","llmSpecific":false,"classifierConfidence":0.85,"researchCategory":null,"atlasIds":null,"fixes":[{"ecosystem":"go","name":"github.com/sonirico/mcp-shell","fixedVersion":"0.6.0","matchedVersion":"v0.6.0","fixReleasedAt":"2026-06-14T11:30:25.000Z","daysToFix":-72,"match":"ecosystem","source":"registry","status":"found","checkedAt":"2026-10-29T21:31:15.639Z"}]}}