{"id":"CVE-2026-81096","state":"PUBLISHED","title":"ToolUniverse through 1.2.6 Unauthenticated Remote Code Execution via python_code_executor Sandbox Escape","description":"ToolUniverse ran caller-supplied Python inside a sandbox that could be escaped, on a server that required no authentication. The executor behind the python_code_executor tool, in python_executor_tool.py, inspected the submitted source for a denied list of attribute names and calls but left the attribute-lookup builtins available and did not stop a dunder attribute reached through a string lookup or through a module already permitted, so a caller could walk from a literal's class to its base and enumerate subclasses to obtain a reference to the process and subprocess modules. A per-call argument also let the caller widen the import allow-list before the inspection ran. The HTTP and MCP servers in http_api_server.py and smcp_server.py bound to every interface with debugging enabled and no authentication, so any caller able to reach the port executed code as the server process. Version 1.3.0 adds bearer-token authentication, defaults the bind address to loopback, and hardens the attribute checks.","publishedAt":"2026-08-27T14:50:36.897Z","updatedAt":"2026-08-29T11:48:10.764Z","severity":{"score":9.3,"label":"Critical","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["mims-harvard ToolUniverse"],"affected":[{"vendor":"mims-harvard","product":"ToolUniverse","packageURL":"pkg:pypi/tooluniverse","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"1.2.6","versionType":"semver"}],"collectionURL":"https://github.com/mims-harvard/ToolUniverse","repo":"https://github.com/mims-harvard/ToolUniverse"}],"references":["https://github.com/mims-harvard/ToolUniverse","https://github.com/mims-harvard/ToolUniverse/pull/251","https://github.com/mims-harvard/ToolUniverse/security/advisories/GHSA-pxwq-22vf-87fm","https://www.vulncheck.com/advisories/tooluniverse-through-1.2.6-unauthenticated-remote-code-execution-via-python-code-executor-sandbox-escape"],"weaknesses":["CWE-94"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/81xxx/CVE-2026-81096.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-81096","state":"PUBLISHED","datePublished":"2026-08-27T14:50:36.897Z","dateUpdated":"2026-08-29T11:48:10.764Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-08-26T16:00:32.344Z"},"containers":{"cna":{"title":"ToolUniverse through 1.2.6 Unauthenticated Remote Code Execution via python_code_executor Sandbox Escape","descriptions":[{"lang":"en","value":"ToolUniverse ran caller-supplied Python inside a sandbox that could be escaped, on a server that required no authentication. The executor behind the python_code_executor tool, in python_executor_tool.py, inspected the submitted source for a denied list of attribute names and calls but left the attribute-lookup builtins available and did not stop a dunder attribute reached through a string lookup or through a module already permitted, so a caller could walk from a literal's class to its base and enumerate subclasses to obtain a reference to the process and subprocess modules. A per-call argument also let the caller widen the import allow-list before the inspection ran. The HTTP and MCP servers in http_api_server.py and smcp_server.py bound to every interface with debugging enabled and no authentication, so any caller able to reach the port executed code as the server process. Version 1.3.0 adds bearer-token authentication, defaults the bind address to loopback, and hardens the attribute checks."}],"affected":[{"vendor":"mims-harvard","product":"ToolUniverse","packageURL":"pkg:pypi/tooluniverse","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"1.2.6","versionType":"semver"}],"collectionURL":"https://github.com/mims-harvard/ToolUniverse","repo":"https://github.com/mims-harvard/ToolUniverse"}],"references":[{"url":"https://github.com/mims-harvard/ToolUniverse","tags":["product"]},{"url":"https://github.com/mims-harvard/ToolUniverse/pull/251","tags":["issue-tracking","patch"]},{"url":"https://github.com/mims-harvard/ToolUniverse/security/advisories/GHSA-pxwq-22vf-87fm","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-pxwq-22vf-87fm)"},{"url":"https://www.vulncheck.com/advisories/tooluniverse-through-1.2.6-unauthenticated-remote-code-execution-via-python-code-executor-sandbox-escape","name":"VulnCheck Advisory: ToolUniverse through 1.2.6 Unauthenticated Remote Code Execution via python_code_executor Sandbox Escape","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"CRITICAL","baseScore":9.3,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"}},{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","version":"3.1","baseSeverity":"CRITICAL","baseScore":10,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-94","lang":"en","description":"Improper Control of Generation of Code ('Code Injection')","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-08-29T11:48:10.764Z"},"datePublic":"2026-08-26T00:00:00.000Z","credits":[{"lang":"en","value":"Avishai Gonen (Pluto Security)","type":"finder"}],"x_generator":{"engine":"vulncheck-endgame"},"source":{"discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-27T18:13:07.150435Z","id":"CVE-2026-81096","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-27T18:13:19.374Z"}}]}}}