{"id":"CVE-2026-106439","state":"PUBLISHED","title":"Hydra: Mutable instantiate policy sets allow target blocklist bypass","description":"Hydra is a framework for elegantly configuring complex applications. From 1.3.4 until 1.3.7 and 1.4.0.dev10, Hydra stores legacy instantiate target blocklists and related execution-policy collections in mutable module-level state. An attacker who controls multiple sibling target entries can resolve hydra._internal.target_policy.UNCONTROLLED_EXECUTION_TARGETS.discard through instantiate(), remove a denied target, and then invoke that target because sibling nodes are processed in insertion order against the same modified policy. The mutation persists in process-global state and can enable code execution with the application's privileges, while a narrow execution whitelist supplied by trusted Python code is not bypassed by the reported direct mutation path. This issue is fixed in versions 1.3.7 and 1.4.0.dev10.","publishedAt":"2026-10-06T18:49:12.110Z","updatedAt":"2026-10-06T19:48:45.736Z","severity":{"score":8.5,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["hydra-ecosystem hydra"],"affected":[{"vendor":"hydra-ecosystem","product":"hydra","versions":[{"version":">= 1.3.4, < 1.3.7","status":"affected"},{"version":">= 1.4.0.dev4, < 1.4.0.dev10","status":"affected"}]}],"references":["https://github.com/hydra-ecosystem/hydra/security/advisories/GHSA-mwj6-rfh8-7qf4","https://github.com/hydra-ecosystem/hydra/commit/0dd18084589a3d3e577d1f1a8a48fb485c94a5e6","https://github.com/hydra-ecosystem/hydra/commit/4720dfca2bde27fa140ec287a05709668fbdf168","https://github.com/hydra-ecosystem/hydra/releases/tag/v1.3.7"],"weaknesses":["CWE-470","CWE-693"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/106xxx/CVE-2026-106439.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-106439","state":"PUBLISHED","datePublished":"2026-10-06T18:49:12.110Z","dateUpdated":"2026-10-06T19:48:45.736Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-06T16:49:40.590Z"},"containers":{"cna":{"title":"Hydra: Mutable instantiate policy sets allow target blocklist bypass","descriptions":[{"lang":"en","value":"Hydra is a framework for elegantly configuring complex applications. From 1.3.4 until 1.3.7 and 1.4.0.dev10, Hydra stores legacy instantiate target blocklists and related execution-policy collections in mutable module-level state. An attacker who controls multiple sibling target entries can resolve hydra._internal.target_policy.UNCONTROLLED_EXECUTION_TARGETS.discard through instantiate(), remove a denied target, and then invoke that target because sibling nodes are processed in insertion order against the same modified policy. The mutation persists in process-global state and can enable code execution with the application's privileges, while a narrow execution whitelist supplied by trusted Python code is not bypassed by the reported direct mutation path. This issue is fixed in versions 1.3.7 and 1.4.0.dev10."}],"affected":[{"vendor":"hydra-ecosystem","product":"hydra","versions":[{"version":">= 1.3.4, < 1.3.7","status":"affected"},{"version":">= 1.4.0.dev4, < 1.4.0.dev10","status":"affected"}]}],"references":[{"url":"https://github.com/hydra-ecosystem/hydra/security/advisories/GHSA-mwj6-rfh8-7qf4","name":"https://github.com/hydra-ecosystem/hydra/security/advisories/GHSA-mwj6-rfh8-7qf4","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/hydra-ecosystem/hydra/commit/0dd18084589a3d3e577d1f1a8a48fb485c94a5e6","name":"https://github.com/hydra-ecosystem/hydra/commit/0dd18084589a3d3e577d1f1a8a48fb485c94a5e6","tags":["x_refsource_MISC"]},{"url":"https://github.com/hydra-ecosystem/hydra/commit/4720dfca2bde27fa140ec287a05709668fbdf168","name":"https://github.com/hydra-ecosystem/hydra/commit/4720dfca2bde27fa140ec287a05709668fbdf168","tags":["x_refsource_MISC"]},{"url":"https://github.com/hydra-ecosystem/hydra/releases/tag/v1.3.7","name":"https://github.com/hydra-ecosystem/hydra/releases/tag/v1.3.7","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"LOCAL","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.5,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-470","lang":"en","description":"CWE-470: Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-693","lang":"en","description":"CWE-693: Protection Mechanism Failure","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-06T18:49:12.110Z"},"source":{"advisory":"GHSA-mwj6-rfh8-7qf4","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/hydra-ecosystem/hydra/security/advisories/GHSA-mwj6-rfh8-7qf4","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-06T19:48:26.207340Z","id":"CVE-2026-106439","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-06T19:48:45.736Z"}}]}}}