{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-50029", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-02T22:46:02.580Z", "datePublished": "2026-08-14T19:08:54.941Z", "dateUpdated": "2026-08-14T19:08:54.941Z"}, "containers": {"cna": {"title": "js-toml has silent type confusion via falsy-primitive duplicate-key bypass", "problemTypes": [{"descriptions": [{"cweId": "CWE-697", "lang": "en", "description": "CWE-697: Incorrect Comparison", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/sunnyadn/js-toml/security/advisories/GHSA-m34p-749j-x6m6", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/sunnyadn/js-toml/security/advisories/GHSA-m34p-749j-x6m6"}, {"name": "https://github.com/sunnyadn/js-toml/commit/e0504fa5d3dcde2d1d588c9001c24b7b700beeeb", "tags": ["x_refsource_MISC"], "url": "https://github.com/sunnyadn/js-toml/commit/e0504fa5d3dcde2d1d588c9001c24b7b700beeeb"}, {"name": "https://github.com/sunnyadn/js-toml/releases/tag/v1.1.2", "tags": ["x_refsource_MISC"], "url": "https://github.com/sunnyadn/js-toml/releases/tag/v1.1.2"}], "affected": [{"vendor": "sunnyadn", "product": "js-toml", "versions": [{"version": "< 1.1.2", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-14T19:08:54.941Z"}, "descriptions": [{"lang": "en", "value": "js-toml is a TOML parser for JavaScript, Prior to version 1.1.2, the interpreter checks whether a key already exists in a parser-built container with `if (object[key])` instead of `if (key in object)`. When the prior value is a falsy primitive \u2014 `false`, `0`, `0n`, `0.0`, `-0`, or `\"\"` \u2014 the duplicate-key branch is skipped and the value is silently overwritten by a later sub-table, dotted-key sub-table, or array-of-tables sharing the same name. Per the TOML 1.0.0 spec (\"Defining a key multiple times is invalid\"; \"You cannot define any key or table more than once\"), this should be a parse error. The result is structural type confusion of attacker-named keys in the value returned by `load()`. A boolean-typed `false` (or numeric `0`) becomes a truthy object. Host applications that gate behavior on `if (config.flag)`, `if (!user.banned)`, `if (config.allowDelete)`, or `if (config.publicMode)` will silently take the truthy branch. This is distinct from GHSA-65fc-cr5f-v7r2 (the 1.0.2 prototype-pollution fix). `Object.prototype` is not polluted. The `Object.create(null)` mitigation from 1.0.2 is intact; the bug here is in the duplicate-key state machine, not in container construction. Version 1.1.2 patches the incorrect comparison."}], "source": {"advisory": "GHSA-m34p-749j-x6m6", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "js-toml", "vendor": "sunnyadn", "versions": [{"status": "affected", "version": "< 1.1.2"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "js-toml is a TOML parser for JavaScript, Prior to version 1.1.2, the interpreter checks whether a key already exists in a parser-built container with `if (object[key])` instead of `if (key in object)`. When the prior value is a falsy primitive \u2014 `false`, `0`, `0n`, `0.0`, `-0`, or `\"\"` \u2014 the duplicate-key branch is skipped and the value is silently overwritten by a later sub-table, dotted-key sub-table, or array-of-tables sharing the same name. Per the TOML 1.0.0 spec (\"Defining a key multiple times is invalid\"; \"You cannot define any key or table more than once\"), this should be a parse error. The result is structural type confusion of attacker-named keys in the value returned by `load()`. A boolean-typed `false` (or numeric `0`) becomes a truthy object. Host applications that gate behavior on `if (config.flag)`, `if (!user.banned)`, `if (config.allowDelete)`, or `if (config.publicMode)` will silently take the truthy branch. This is distinct from GHSA-65fc-cr5f-v7r2 (the 1.0.2 prototype-pollution fix). `Object.prototype` is not polluted. The `Object.create(null)` mitigation from 1.0.2 is intact; the bug here is in the duplicate-key state machine, not in container construction. Version 1.1.2 patches the incorrect comparison."}], "id": "CVE-2026-50029", "lastModified": "2026-08-14T19:17:18.980", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-08-14T19:17:18.980", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/sunnyadn/js-toml/commit/e0504fa5d3dcde2d1d588c9001c24b7b700beeeb"}, {"source": "security-advisories@github.com", "url": "https://github.com/sunnyadn/js-toml/releases/tag/v1.1.2"}, {"source": "security-advisories@github.com", "url": "https://github.com/sunnyadn/js-toml/security/advisories/GHSA-m34p-749j-x6m6"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-697"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}