{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-91776",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-91776",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-09-23T02:17:50.480Z",
    "updatedAt": "2026-09-23T14:03:16.129Z",
    "importedAt": "2026-10-24T01:58:35.090Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "jackson-databind: unbounded growth of the type id cache in TypeDeserializerBase retains every unknown raw type ID",
      "summary": "TypeDeserializerBase._findDeserializer() in FasterXML jackson-databind caches the resolved deserializer under the raw, attacker-supplied type ID. When name-based polymorphism is configured with a fallback, for example @JsonTypeInfo(use = Id.NAME, defaultImpl = ...), every distinct unrecognized type ID resolves to the same fallback deserializer but is retained as its own key in the _deserializers map. That map has no configurable bound and lives for the lifetime of the type deserializer, so an attacker who can repeatedly supply fresh unknown type IDs causes monotonic memory retention across requests. The reporter observed 10,000 retained entries from 10,000 distinct unknown IDs, against a single entry for a control that repeated one unknown ID the same number of times, isolating attacker-controlled key cardinality from request volume. Exploitation requires an application that enables name-based polymorphism with a defaultImpl or equivalent fallback, accepts attacker-influenced type IDs, and reuses a long-lived ObjectMapper across requests. The fix stops caching fallback resolutions for unrecognized IDs and bounds both the number of cached entries and the length of a cacheable type ID.",
      "affected": [
        {
          "vendor": "FasterXML",
          "product": "jackson-databind",
          "packageName": "com.fasterxml.jackson.core:jackson-databind",
          "collectionURL": "https://repo1.maven.org/maven2",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "2.0.0",
              "status": "affected",
              "versionType": "maven",
              "lessThanOrEqual": "2.18.10"
            },
            {
              "version": "2.19.0",
              "status": "affected",
              "versionType": "maven",
              "lessThanOrEqual": "2.21.6"
            },
            {
              "version": "2.22.0",
              "status": "affected",
              "versionType": "maven",
              "lessThanOrEqual": "2.22.2"
            }
          ]
        },
        {
          "vendor": "FasterXML",
          "product": "jackson-databind",
          "packageName": "tools.jackson.core:jackson-databind",
          "collectionURL": "https://repo1.maven.org/maven2",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "3.0.0",
              "status": "affected",
              "versionType": "maven",
              "lessThanOrEqual": "3.1.6"
            },
            {
              "version": "3.2.0",
              "status": "affected",
              "versionType": "maven",
              "lessThanOrEqual": "3.2.2"
            }
          ]
        }
      ]
    }
  }
}