{"cve":"CVE-2026-54512","nvd":{"published":"2026-06-23T21:17:02.203","modified":"2026-10-25T23:10:00.167","status":"Analyzed","description":"jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.10.0 until 2.18.8, 2.21.4, and 3.1.4, jackson-databind's PolymorphicTypeValidator (PTV) is the primary safety mechanism guarding polymorphic deserialization. When polymorphic typing is enabled and a type identifier contains generic parameters (i.e. the type ID string contains <), DatabindContext._resolveAndValidateGeneric() validates only the raw container class name (the substring before <) against the configured PTV. If the container type is approved, the method parses the full canonical type string via TypeFactory.constructFromCanonical() and returns the fully parameterized type without ever validating the nested type arguments against the PTV. The nested type arguments are then resolved, instantiated, and populated as beans during deserialization. An attacker who controls the type ID can therefore place a denied class as a generic type parameter of an allowed container — for example java.util.ArrayList<com.evil.Gadget> when only java.util.ArrayList is allow-listed. The container passes the PTV check; com.evil.Gadget is loaded via Class.forName(name, true, loader), instantiated, and its properties are set from attacker-controlled JSON. This completely bypasses an explicitly configured PTV allow-list. This vulnerability is fixed in 2.18.8, 2.21.4, and 3.1.4.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1},"cwes":["CWE-184","CWE-502"],"references":["https://github.com/FasterXML/jackson-databind/commit/434d6c511de7fdd9872f29157aafb6162d12d8d5","https://github.com/FasterXML/jackson-databind/issues/5988","https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-j3rv-43j4-c7qm","https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-j3rv-43j4-c7qm"],"products":["fasterxml:jackson-databind"],"source":"nvd","synced_at":"2026-10-25T23:44:33.281319194+00:00"},"epss":{"cve":"CVE-2026-54512","score":0.00944,"percentile":0.60805,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-j3rv-43j4-c7qm","url":"https://osv.dev/vulnerability/GHSA-j3rv-43j4-c7qm","summary":"jackson-databind has a PolymorphicTypeValidator bypass via generic type parameters that allows arbitrary class instantiation","modified":"2026-09-10T03:50:50.187641487Z","packages":[{"ecosystem":"Maven","name":"com.fasterxml.jackson.core:jackson-databind","purl":"pkg:maven/com.fasterxml.jackson.core/jackson-databind","ranges":[">=2.10.0 <2.18.8"],"fixed":["2.18.8"]},{"ecosystem":"Maven","name":"com.fasterxml.jackson.core:jackson-databind","purl":"pkg:maven/com.fasterxml.jackson.core/jackson-databind","ranges":[">=3.0.0 <3.1.4"],"fixed":["3.1.4"]},{"ecosystem":"Maven","name":"com.fasterxml.jackson.core:jackson-databind","purl":"pkg:maven/com.fasterxml.jackson.core/jackson-databind","ranges":[">=2.19.0 <2.21.4"],"fixed":["2.21.4"]},{"ecosystem":"Maven","name":"tools.jackson.core:jackson-databind","purl":"pkg:maven/tools.jackson.core/jackson-databind","ranges":[">=3.0.0 <3.1.4"],"fixed":["3.1.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}