{"id":"CVE-2026-53541","state":"PUBLISHED","title":"OliveTin has Unvalidated `ot_`-prefixed Arguments that Bypass Input Filtering","description":"OliveTin gives access to predefined shell commands from a web interface. The `filterToDefinedArgumentsOnly` function in the executor is intended to discard any arguments not explicitly defined in the action's configuration. However, prior to commit ebffd9f040f791208aee1db2e5a8aecd1e3e603d, a special case allows any argument whose name starts with `ot_` to bypass this filter. While two system arguments (`ot_executionTrackingId` and `ot_username`) are injected by OliveTin and overridden, all other `ot_`-prefixed arguments supplied by the user pass through unmodified. These bypassed arguments are not type-checked — the validation loop only iterates over the action's defined arguments, so `ot_`-prefixed arguments skip all type safety checks entirely; set as environment variables — via `buildEnv()`, with completely unvalidated values, and passed to the executed command; and included in the template context — available as `.Arguments.ot_*` in template rendering. Commit ebffd9f040f791208aee1db2e5a8aecd1e3e603d contains a patch.","publishedAt":"2026-08-21T22:51:52.752Z","updatedAt":"2026-08-24T20:03:47.277Z","severity":{"score":4.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["OliveTin OliveTin"],"affected":[{"vendor":"OliveTin","product":"OliveTin","versions":[{"version":"<= 2025.03.07","status":"affected"}]}],"references":["https://github.com/OliveTin/OliveTin/security/advisories/GHSA-prj9-97mp-mwh2","https://github.com/OliveTin/OliveTin/commit/ebffd9f040f791208aee1db2e5a8aecd1e3e603d"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53541.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53541","state":"PUBLISHED","datePublished":"2026-08-21T22:51:52.752Z","dateUpdated":"2026-08-24T20:03:47.277Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-09T18:13:07.263Z"},"containers":{"cna":{"title":"OliveTin has Unvalidated `ot_`-prefixed Arguments that Bypass Input Filtering","descriptions":[{"lang":"en","value":"OliveTin gives access to predefined shell commands from a web interface. The `filterToDefinedArgumentsOnly` function in the executor is intended to discard any arguments not explicitly defined in the action's configuration. However, prior to commit ebffd9f040f791208aee1db2e5a8aecd1e3e603d, a special case allows any argument whose name starts with `ot_` to bypass this filter. While two system arguments (`ot_executionTrackingId` and `ot_username`) are injected by OliveTin and overridden, all other `ot_`-prefixed arguments supplied by the user pass through unmodified. These bypassed arguments are not type-checked — the validation loop only iterates over the action's defined arguments, so `ot_`-prefixed arguments skip all type safety checks entirely; set as environment variables — via `buildEnv()`, with completely unvalidated values, and passed to the executed command; and included in the template context — available as `.Arguments.ot_*` in template rendering. Commit ebffd9f040f791208aee1db2e5a8aecd1e3e603d contains a patch."}],"affected":[{"vendor":"OliveTin","product":"OliveTin","versions":[{"version":"<= 2025.03.07","status":"affected"}]}],"references":[{"url":"https://github.com/OliveTin/OliveTin/security/advisories/GHSA-prj9-97mp-mwh2","name":"https://github.com/OliveTin/OliveTin/security/advisories/GHSA-prj9-97mp-mwh2","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/OliveTin/OliveTin/commit/ebffd9f040f791208aee1db2e5a8aecd1e3e603d","name":"https://github.com/OliveTin/OliveTin/commit/ebffd9f040f791208aee1db2e5a8aecd1e3e603d","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","description":"CWE-20: Improper Input Validation","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-21T22:51:52.752Z"},"source":{"advisory":"GHSA-prj9-97mp-mwh2","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/OliveTin/OliveTin/security/advisories/GHSA-prj9-97mp-mwh2","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-24T20:03:40.743318Z","id":"CVE-2026-53541","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-24T20:03:47.277Z"}}]}}}