{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-41316", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-04-20T14:01:46.671Z", "datePublished": "2026-04-24T02:35:41.160Z", "dateUpdated": "2026-04-24T02:35:41.160Z"}, "containers": {"cna": {"title": "ERB has an @_init deserialization guard bypass via def_module / def_method / def_class", "problemTypes": [{"descriptions": [{"cweId": "CWE-693", "lang": "en", "description": "CWE-693: Protection Mechanism Failure", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/ruby/erb/security/advisories/GHSA-q339-8rmv-2mhv", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/ruby/erb/security/advisories/GHSA-q339-8rmv-2mhv"}], "affected": [{"vendor": "ruby", "product": "erb", "versions": [{"version": "< 4.0.3.1", "status": "affected"}, {"version": "= 4.0.4", "status": "affected"}, {"version": ">= 5.0.0, < 6.0.1.1", "status": "affected"}, {"version": ">= 6.0.2, < 6.0.4", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-04-24T02:35:41.160Z"}, "descriptions": [{"lang": "en", "value": "ERB is a templating system for Ruby. Ruby 2.7.0 (before ERB 2.2.0 was published on rubygems.org) introduced an `@_init` instance variable guard in `ERB#result` and `ERB#run` to prevent code execution when an ERB object is reconstructed via `Marshal.load` (deserialization). However, three other public methods that also evaluate `@src` via `eval()` were not given the same guard: `ERB#def_method`, `ERB#def_module`, and `ERB#def_class`. An attacker who can trigger `Marshal.load` on untrusted data in a Ruby application that has `erb` loaded can use `ERB#def_module` (zero-arg, default parameters) as a code execution sink, bypassing the `@_init` protection entirely. ERB 4.0.3.1, 4.0.4.1, 6.0.1.1, and 6.0.4 patch the issue."}], "source": {"advisory": "GHSA-q339-8rmv-2mhv", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "ERB is a templating system for Ruby. Ruby 2.7.0 (before ERB 2.2.0 was published on rubygems.org) introduced an `@_init` instance variable guard in `ERB#result` and `ERB#run` to prevent code execution when an ERB object is reconstructed via `Marshal.load` (deserialization). However, three other public methods that also evaluate `@src` via `eval()` were not given the same guard: `ERB#def_method`, `ERB#def_module`, and `ERB#def_class`. An attacker who can trigger `Marshal.load` on untrusted data in a Ruby application that has `erb` loaded can use `ERB#def_module` (zero-arg, default parameters) as a code execution sink, bypassing the `@_init` protection entirely. ERB 4.0.3.1, 4.0.4.1, 6.0.1.1, and 6.0.4 patch the issue."}], "id": "CVE-2026-41316", "lastModified": "2026-04-24T03:16:11.897", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 5.9, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-04-24T03:16:11.897", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/ruby/erb/security/advisories/GHSA-q339-8rmv-2mhv"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-693"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}