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GHSA-9FXM-VC8V-HJ55

Vulnerability from github – Published: 2026-06-23 21:24 – Updated: 2026-07-20 21:21
VLAI
Summary
jackson-databind's renamed @JsonIgnore'd setters can deserialize via private fields
Details

Summary

POJOPropertiesCollector._renameProperties() allows a property with @JsonProperty("renamed") on the getter and @JsonIgnore on the setter to be renamed rather than dropped. With MapperFeature.INFER_PROPERTY_MUTATORS enabled (default), the private backing field is retained; during deserialization BeanDeserializerFactory.addBeanProps() sees hasField()==true, builds a FieldProperty, and makes the backing field writable. An attacker supplying the renamed JSON key writes the backing field directly, bypassing the @JsonIgnore on the setter.

Impact

POJOs combining a renamed getter with an ignored setter (a read-only-over-the-wire pattern) have that field silently set from attacker input (property tampering / mass assignment). Not a general gadget; no RCE.

Affected / Patched (verified via git tag --contains)

  • 2.21 line: >= 2.21.0, < 2.21.4 -> fixed in 2.21.4 (backport c3d56dd, #5968)
  • 3.x line: >= 3.0.0, < 3.1.4 -> fixed in 3.1.4 (#5967, e88cb17)

Severity / CWE

Maintainer: minor. Reporter: HIGH. CWE-915.

Credits

Omkhar Arasaratnam (@omkhar) - finder.

Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "com.fasterxml.jackson.core:jackson-databind"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.21.0"
            },
            {
              "fixed": "2.21.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "com.fasterxml.jackson.core:jackson-databind"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "3.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "tools.jackson.core:jackson-databind"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "3.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-54516"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-915"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-23T21:24:26Z",
    "nvd_published_at": "2026-06-23T21:17:02Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n`POJOPropertiesCollector._renameProperties()` allows a property with `@JsonProperty(\"renamed\")` on the getter and `@JsonIgnore` on the setter to be renamed rather than dropped. With `MapperFeature.INFER_PROPERTY_MUTATORS` enabled (default), the private backing field is retained; during deserialization `BeanDeserializerFactory.addBeanProps()` sees `hasField()==true`, builds a `FieldProperty`, and makes the backing field writable. An attacker supplying the renamed JSON key writes the backing field directly, bypassing the `@JsonIgnore` on the setter.\n\n## Impact\nPOJOs combining a renamed getter with an ignored setter (a read-only-over-the-wire pattern) have that field silently set from attacker input (property tampering / mass assignment). Not a general gadget; no RCE.\n\n## Affected / Patched (verified via `git tag --contains`)\n- 2.21 line: `\u003e= 2.21.0, \u003c 2.21.4` -\u003e fixed in **2.21.4** (backport `c3d56dd`, #5968)\n- 3.x line: `\u003e= 3.0.0, \u003c 3.1.4` -\u003e fixed in **3.1.4** (#5967, `e88cb17`)\n\n## Severity / CWE\nMaintainer: minor. Reporter: HIGH. CWE-915.\n\n## Credits\nOmkhar Arasaratnam (@omkhar) - finder.",
  "id": "GHSA-9fxm-vc8v-hj55",
  "modified": "2026-07-20T21:21:24Z",
  "published": "2026-06-23T21:24:26Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-9fxm-vc8v-hj55"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54516"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FasterXML/jackson-databind/pull/5967"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FasterXML/jackson-databind/pull/5968"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FasterXML/jackson-databind/commit/c3d56dd25d52319828147c5b9aeabf2d485c250a"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FasterXML/jackson-databind/commit/e88cb17006b6af4883b973058f0bb6486e5074af"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/FasterXML/jackson-databind"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "jackson-databind\u0027s renamed @JsonIgnore\u0027d setters can deserialize via private fields"
}



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