CVE-2026-56817 (GCVE-0-2026-56817)
Vulnerability from cvelistv5
Published
2026-07-21 22:06
Modified
2026-07-22 15:42
CWE
  • CWE-611 - Improper Restriction of XML External Entity Reference
Summary
Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, any caller that can deliver bytes to a Netty channel pipeline containing `XmlDecoder` can send XML with a `DOCTYPE` declaration to an `AsyncXMLInputFactory` instantiated with no security configuration, leaving DTD and entity handling active depending on Aalto XML async parser behavior and creating conditional XML external entity risk. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.
Impacted products
Vendor Product Version
netty netty Version: >= 4.2.0.Final, < 4.2.16.Final
Version: >= 4.1.0.Final, < 4.1.136.Final
Create a notification for this product.
Show details on NVD website


{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-56817",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-22T15:40:54.756346Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-22T15:42:09.445Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "netty",
          "vendor": "netty",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 4.2.0.Final, \u003c 4.2.16.Final"
            },
            {
              "status": "affected",
              "version": "\u003e= 4.1.0.Final, \u003c 4.1.136.Final"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, any caller that can deliver bytes to a Netty channel pipeline containing `XmlDecoder` can send XML with a `DOCTYPE` declaration to an `AsyncXMLInputFactory` instantiated with no security configuration, leaving DTD and entity handling active depending on Aalto XML async parser behavior and creating conditional XML external entity risk. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 8.3,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-611",
              "description": "CWE-611: Improper Restriction of XML External Entity Reference",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-21T22:06:56.481Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx"
        },
        {
          "name": "https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b"
        },
        {
          "name": "https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6"
        },
        {
          "name": "https://github.com/netty/netty/releases/tag/netty-4.1.136.Final",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/netty/netty/releases/tag/netty-4.1.136.Final"
        },
        {
          "name": "https://github.com/netty/netty/releases/tag/netty-4.2.16.Final",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/netty/netty/releases/tag/netty-4.2.16.Final"
        }
      ],
      "source": {
        "advisory": "GHSA-4qhr-g3c6-fcfx",
        "discovery": "UNKNOWN"
      },
      "title": "Netty: XML External Entity (XXE) injection via unconfigured XML factory when DTD and entity processing are enabled"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-56817",
    "datePublished": "2026-07-21T22:06:56.481Z",
    "dateReserved": "2026-06-23T14:55:09.116Z",
    "dateUpdated": "2026-07-22T15:42:09.445Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"cna\": {\"title\": \"Netty: XML External Entity (XXE) injection via unconfigured XML factory when DTD and entity processing are enabled\", \"problemTypes\": [{\"descriptions\": [{\"cweId\": \"CWE-611\", \"lang\": \"en\", \"description\": \"CWE-611: Improper Restriction of XML External Entity Reference\", \"type\": \"CWE\"}]}], \"metrics\": [{\"cvssV4_0\": {\"attackVector\": \"NETWORK\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"NONE\", \"vulnConfidentialityImpact\": \"HIGH\", \"vulnIntegrityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"LOW\", \"subConfidentialityImpact\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"baseScore\": 8.3, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N\", \"version\": \"4.0\"}}], \"references\": [{\"name\": \"https://github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx\", \"tags\": [\"x_refsource_CONFIRM\"], \"url\": \"https://github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx\"}, {\"name\": \"https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b\", \"tags\": [\"x_refsource_MISC\"], \"url\": \"https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b\"}, {\"name\": \"https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6\", \"tags\": [\"x_refsource_MISC\"], \"url\": \"https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6\"}, {\"name\": \"https://github.com/netty/netty/releases/tag/netty-4.1.136.Final\", \"tags\": [\"x_refsource_MISC\"], \"url\": \"https://github.com/netty/netty/releases/tag/netty-4.1.136.Final\"}, {\"name\": \"https://github.com/netty/netty/releases/tag/netty-4.2.16.Final\", \"tags\": [\"x_refsource_MISC\"], \"url\": \"https://github.com/netty/netty/releases/tag/netty-4.2.16.Final\"}], \"affected\": [{\"vendor\": \"netty\", \"product\": \"netty\", \"versions\": [{\"version\": \"\u003e= 4.2.0.Final, \u003c 4.2.16.Final\", \"status\": \"affected\"}, {\"version\": \"\u003e= 4.1.0.Final, \u003c 4.1.136.Final\", \"status\": \"affected\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-07-21T22:06:56.481Z\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, any caller that can deliver bytes to a Netty channel pipeline containing `XmlDecoder` can send XML with a `DOCTYPE` declaration to an `AsyncXMLInputFactory` instantiated with no security configuration, leaving DTD and entity handling active depending on Aalto XML async parser behavior and creating conditional XML external entity risk. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.\"}], \"source\": {\"advisory\": \"GHSA-4qhr-g3c6-fcfx\", \"discovery\": \"UNKNOWN\"}}, \"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-56817\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-22T15:40:54.756346Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-22T15:42:04.094Z\"}}]}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-56817\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"state\": \"PUBLISHED\", \"assignerShortName\": \"GitHub_M\", \"dateReserved\": \"2026-06-23T14:55:09.116Z\", \"datePublished\": \"2026-07-21T22:06:56.481Z\", \"dateUpdated\": \"2026-07-22T15:42:09.445Z\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


Loading…

Loading…