{"api_version":"1","generated_at":"2026-04-17T02:00:40+00:00","cve":"CVE-2026-39421","urls":{"html":"https://cve.report/CVE-2026-39421","api":"https://cve.report/api/cve/CVE-2026-39421.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-39421","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-39421"},"summary":{"title":"MaxKB: Sandbox escape via ctypes and unhooked SYS_pkey_mprotect","description":"MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a sandbox escape vulnerability in the ToolExecutor component. By leveraging Python's ctypes library to execute raw system calls, an authenticated attacker with workspace privileges can bypass the LD_PRELOAD-based sandbox.so module to achieve arbitrary code execution via direct kernel system calls, enabling full network exfiltration and container compromise. The library intercepts critical standard system functions such as execve, system, connect, and open. It also intercepts mprotect to prevent PROT_EXEC (executable memory) allocations within the sandboxed Python processes, but pkey_mprotect is not blocked. This issue has been fixed in version 2.8.0.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-04-14 01:16:04","updated_at":"2026-04-14 01:16:04"},"problem_types":["CWE-94","CWE-693","CWE-693 CWE-693: Protection Mechanism Failure","CWE-94 CWE-94: Improper Control of Generation of Code ('Code Injection')"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"6.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","baseScore":6.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"LOW"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"6.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":6.3,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","version":"3.1"}}],"references":[{"url":"https://github.com/1Panel-dev/MaxKB/commit/479701a4d2e6059506bad0057a66bed91abb5aef","name":"https://github.com/1Panel-dev/MaxKB/commit/479701a4d2e6059506bad0057a66bed91abb5aef","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0","name":"https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-9c6w-j7w5-3gf7","name":"https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-9c6w-j7w5-3gf7","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-39421","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39421","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"1Panel-dev","product":"MaxKB","version":"affected < 2.8.0","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"39421","cve":"CVE-2026-39421","epss":"0.000740000","percentile":"0.223570000","score_date":"2026-04-15","updated_at":"2026-04-16 00:13:56"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"MaxKB","vendor":"1Panel-dev","versions":[{"status":"affected","version":"< 2.8.0"}]}],"descriptions":[{"lang":"en","value":"MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a sandbox escape vulnerability in the ToolExecutor component. By leveraging Python's ctypes library to execute raw system calls, an authenticated attacker with workspace privileges can bypass the LD_PRELOAD-based sandbox.so module to achieve arbitrary code execution via direct kernel system calls, enabling full network exfiltration and container compromise. The library intercepts critical standard system functions such as execve, system, connect, and open. It also intercepts mprotect to prevent PROT_EXEC (executable memory) allocations within the sandboxed Python processes, but pkey_mprotect is not blocked. This issue has been fixed in version 2.8.0."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":6.3,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-693","description":"CWE-693: Protection Mechanism Failure","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-94","description":"CWE-94: Improper Control of Generation of Code ('Code Injection')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-04-14T00:17:10.279Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-9c6w-j7w5-3gf7","tags":["x_refsource_CONFIRM"],"url":"https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-9c6w-j7w5-3gf7"},{"name":"https://github.com/1Panel-dev/MaxKB/commit/479701a4d2e6059506bad0057a66bed91abb5aef","tags":["x_refsource_MISC"],"url":"https://github.com/1Panel-dev/MaxKB/commit/479701a4d2e6059506bad0057a66bed91abb5aef"},{"name":"https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0","tags":["x_refsource_MISC"],"url":"https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0"}],"source":{"advisory":"GHSA-9c6w-j7w5-3gf7","discovery":"UNKNOWN"},"title":"MaxKB: Sandbox escape via ctypes and unhooked SYS_pkey_mprotect"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-39421","datePublished":"2026-04-14T00:17:10.279Z","dateReserved":"2026-04-07T00:23:30.595Z","dateUpdated":"2026-04-14T00:17:10.279Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-14 01:16:04","lastModifiedDate":"2026-04-14 01:16:04","problem_types":["CWE-94","CWE-693","CWE-693 CWE-693: Protection Mechanism Failure","CWE-94 CWE-94: Improper Control of Generation of Code ('Code Injection')"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","baseScore":6.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"LOW"},"exploitabilityScore":2.8,"impactScore":3.4}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"39421","Ordinal":"1","Title":"MaxKB: Sandbox escape via ctypes and unhooked SYS_pkey_mprotect","CVE":"CVE-2026-39421","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"39421","Ordinal":"1","NoteData":"MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a sandbox escape vulnerability in the ToolExecutor component. By leveraging Python's ctypes library to execute raw system calls, an authenticated attacker with workspace privileges can bypass the LD_PRELOAD-based sandbox.so module to achieve arbitrary code execution via direct kernel system calls, enabling full network exfiltration and container compromise. The library intercepts critical standard system functions such as execve, system, connect, and open. It also intercepts mprotect to prevent PROT_EXEC (executable memory) allocations within the sandboxed Python processes, but pkey_mprotect is not blocked. This issue has been fixed in version 2.8.0.","Type":"Description","Title":"MaxKB: Sandbox escape via ctypes and unhooked SYS_pkey_mprotect"}]}}}