{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-56819",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-23T14:55:09.116Z",
        "datePublished": "2026-07-21T22:11:17.470Z",
        "dateUpdated": "2026-07-23T13:55:29.793Z"
    },
    "containers": {
        "cna": {
            "title": "Netty: HTTP/2 decompression leaks ByteBuf reference count when the decompressor channel is already closed (Direct memory leak / OOM DoS)",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-400",
                            "lang": "en",
                            "description": "CWE-400: Uncontrolled Resource Consumption",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-401",
                            "lang": "en",
                            "description": "CWE-401: Missing Release of Memory after Effective Lifetime",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/netty/netty/security/advisories/GHSA-93wv-jw9v-4972",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/netty/netty/security/advisories/GHSA-93wv-jw9v-4972"
                },
                {
                    "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": ">= 4.2.0.Final, < 4.2.16.Final",
                            "status": "affected"
                        },
                        {
                            "version": ">= 4.1.0.Final, < 4.1.136.Final",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-07-22T15:24:49.094Z"
            },
            "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, a remote unauthenticated peer can leak one direct `ByteBuf` per HTTP/2 `DATA` frame in applications that enable HTTP/2 content decompression via `DelegatingDecompressorFrameListener`. When a `DATA` frame is processed for a stream whose decompressor has already been closed, `Http2Decompressor.decompress(...)` calls `decompressor.writeInbound(data.retain())` and does not release the retained buffer on the error path, eventually exhausting direct memory and crashing the JVM. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final."
                }
            ],
            "source": {
                "advisory": "GHSA-93wv-jw9v-4972",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/netty/netty/security/advisories/GHSA-93wv-jw9v-4972",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-23T13:55:20.959839Z",
                                "id": "CVE-2026-56819",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-07-23T13:55:29.793Z"
                }
            }
        ]
    }
}