CVE-2021-43797 (GCVE-0-2021-43797)
Vulnerability from cvelistv5 – Published: 2021-12-09 00:00 – Updated: 2026-10-08 21:13- CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-04T04:03:08.898Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"tags": [
"x_transferred"
],
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"tags": [
"x_transferred"
],
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"tags": [
"x_transferred"
],
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"name": "[debian-lts-announce] 20230111 [SECURITY] [DLA 3268-1] netty security update",
"tags": [
"mailing-list",
"x_transferred"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"name": "DSA-5316",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-43797",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-10-08T21:08:01.062250Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-10-08T21:13:54.692Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "netty",
"vendor": "netty",
"versions": [
{
"status": "affected",
"version": "\u003c= 4.1.7.0.Final"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers \u0026 clients. Netty prior to version 4.1.71.Final skips control chars when they are present at the beginning / end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to \"sanitize\" header names before it forward these to another remote system when used as proxy. This remote system can\u0027t see the invalid usage anymore, and therefore does not do the validation itself. Users should upgrade to version 4.1.71.Final."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-444",
"description": "CWE-444: Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request Smuggling\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2023-01-12T00:00:00.000Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"name": "[debian-lts-announce] 20230111 [SECURITY] [DLA 3268-1] netty security update",
"tags": [
"mailing-list"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"name": "DSA-5316",
"tags": [
"vendor-advisory"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
}
],
"source": {
"advisory": "GHSA-wx5j-54mm-rqqq",
"discovery": "UNKNOWN"
},
"title": "HTTP fails to validate against control chars in header names which may lead to HTTP request smuggling"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2021-43797",
"datePublished": "2021-12-09T00:00:00.000Z",
"dateReserved": "2021-11-16T00:00:00.000Z",
"dateUpdated": "2026-10-08T21:13:54.692Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2021-43797",
"date": "2026-11-13",
"epss": "0.02884",
"percentile": "0.87079"
},
"fkie_nvd": {
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*",
"matchCriteriaId": "F63C0F0C-1D4C-4383-820A-9325DE306780",
"versionEndExcluding": "4.1.71",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:quarkus:quarkus:*:*:*:*:*:*:*:*",
"matchCriteriaId": "9050DC4B-0A83-436F-9AE5-6DC28EC7F69D",
"versionEndExcluding": "2.5.3",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:*",
"matchCriteriaId": "5735E553-9731-4AAC-BCFF-989377F817B3",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:netapp:snapcenter:-:*:*:*:*:*:*:*",
"matchCriteriaId": "BDFB1169-41A0-4A86-8E4F-FDA9730B1E94",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:oracle:banking_deposits_and_lines_of_credit_servicing:2.7:*:*:*:*:*:*:*",
"matchCriteriaId": "ED63D221-31FA-480F-802F-844334F429F5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:banking_party_management:2.7.0:*:*:*:*:*:*:*",
"matchCriteriaId": "C542DC5E-6657-4178-9C69-46FD3C187D56",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:banking_platform:2.6.2:*:*:*:*:*:*:*",
"matchCriteriaId": "132CE62A-FBFC-4001-81EC-35D81F73AF48",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:coherence:12.2.1.4.0:*:*:*:*:*:*:*",
"matchCriteriaId": "2FF57C7A-92C9-4D71-A7B1-CC9DEFAA8193",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:coherence:14.1.1.0.0:*:*:*:*:*:*:*",
"matchCriteriaId": "5FA64A1D-34F9-4441-857A-25C165E6DBB6",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:1.11.0:*:*:*:*:*:*:*",
"matchCriteriaId": "10323322-F6C0-4EA7-9344-736F7A80AA5F",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_network_slice_selection_function:1.8.0:*:*:*:*:*:*:*",
"matchCriteriaId": "3AA09838-BF13-46AC-BB97-A69F48B73A8A",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.15.0:*:*:*:*:*:*:*",
"matchCriteriaId": "B4367D9B-BF81-47AD-A840-AC46317C774D",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_security_edge_protection_proxy:1.7.0:*:*:*:*:*:*:*",
"matchCriteriaId": "BD4349FE-EEF8-489A-8ABF-5FCD55EC6DE0",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_unified_data_repository:1.15.0:*:*:*:*:*:*:*",
"matchCriteriaId": "C6EAA723-2A23-4151-930B-86ACF9CC1C0C",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_design_studio:7.4.2:*:*:*:*:*:*:*",
"matchCriteriaId": "A67AA54B-258D-4D09-9ACB-4085E0B3E585",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_instant_messaging_server:8.1:*:*:*:*:*:*:*",
"matchCriteriaId": "47CE14F1-7E98-4C3B-A817-C54273F23464",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:helidon:1.4.10:*:*:*:*:*:*:*",
"matchCriteriaId": "4E7626D2-D9FF-416A-9581-852CED0D8C24",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:helidon:2.4.0:*:*:*:*:*:*:*",
"matchCriteriaId": "99344A5D-F4B7-49B4-9AE6-0E2FB3874EA5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:*",
"matchCriteriaId": "D9DB4A14-2EF5-4B54-95D2-75E6CF9AA0A9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.59:*:*:*:*:*:*:*",
"matchCriteriaId": "C8AF00C6-B97F-414D-A8DF-057E6BFD8597",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
"matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
"matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers \u0026 clients. Netty prior to version 4.1.71.Final skips control chars when they are present at the beginning / end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to \"sanitize\" header names before it forward these to another remote system when used as proxy. This remote system can\u0027t see the invalid usage anymore, and therefore does not do the validation itself. Users should upgrade to version 4.1.71.Final."
},
{
"lang": "es",
"value": "Netty es un marco de trabajo de aplicaciones de red as\u00edncronas impulsadas por eventos para el desarrollo r\u00e1pido de servidores y clientes de protocolo de alto rendimiento mantenibles. Netty antes de la versi\u00f3n 4.1.71.Final omite los caracteres de control cuando est\u00e1n presentes al principio/fin del nombre de la cabecera. En su lugar, deber\u00eda fallar r\u00e1pidamente ya que estos no est\u00e1n permitidos por la especificaci\u00f3n y podr\u00edan llevar a un contrabando de peticiones HTTP. No hacer la validaci\u00f3n podr\u00eda causar que netty \"sanee\" los nombres de las cabeceras antes de reenviarlas a otro sistema remoto cuando se usa como proxy. Este sistema remoto ya no puede ver el uso inv\u00e1lido, y por lo tanto no hace la validaci\u00f3n por s\u00ed mismo. Los usuarios deben actualizar a la versi\u00f3n 4.1.71.Final"
}
],
"id": "CVE-2021-43797",
"lastModified": "2024-11-21T06:29:48.490",
"metrics": {
"cvssMetricV2": [
{
"acInsufInfo": false,
"baseSeverity": "MEDIUM",
"cvssData": {
"accessComplexity": "MEDIUM",
"accessVector": "NETWORK",
"authentication": "NONE",
"availabilityImpact": "NONE",
"baseScore": 4.3,
"confidentialityImpact": "NONE",
"integrityImpact": "PARTIAL",
"vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
"version": "2.0"
},
"exploitabilityScore": 8.6,
"impactScore": 2.9,
"obtainAllPrivilege": false,
"obtainOtherPrivilege": false,
"obtainUserPrivilege": false,
"source": "nvd@nist.gov",
"type": "Primary",
"userInteractionRequired": true
}
],
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"version": "3.1"
},
"exploitabilityScore": 2.8,
"impactScore": 3.6,
"source": "security-advisories@github.com",
"type": "Secondary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"version": "3.1"
},
"exploitabilityScore": 2.8,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"published": "2021-12-09T19:15:07.960",
"references": [
{
"source": "security-advisories@github.com",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"source": "security-advisories@github.com",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"source": "security-advisories@github.com",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"source": "security-advisories@github.com",
"tags": [
"Third Party Advisory"
],
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"source": "security-advisories@github.com",
"tags": [
"Third Party Advisory"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
},
{
"source": "security-advisories@github.com",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"source": "security-advisories@github.com",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
}
],
"sourceIdentifier": "security-advisories@github.com",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-444"
}
],
"source": "security-advisories@github.com",
"type": "Secondary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-444"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"product": "netty",
"vendor": "netty",
"versions": [
{
"status": "affected",
"version": "\u003c= 4.1.7.0.Final"
}
]
}
],
"source": "security-advisories@github.com"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*",
"matchCriteriaId": "F63C0F0C-1D4C-4383-820A-9325DE306780",
"versionEndExcluding": "4.1.71",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:quarkus:quarkus:*:*:*:*:*:*:*:*",
"matchCriteriaId": "9050DC4B-0A83-436F-9AE5-6DC28EC7F69D",
"versionEndExcluding": "2.5.3",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:*",
"matchCriteriaId": "5735E553-9731-4AAC-BCFF-989377F817B3",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:netapp:snapcenter:-:*:*:*:*:*:*:*",
"matchCriteriaId": "BDFB1169-41A0-4A86-8E4F-FDA9730B1E94",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:oracle:banking_deposits_and_lines_of_credit_servicing:2.7:*:*:*:*:*:*:*",
"matchCriteriaId": "ED63D221-31FA-480F-802F-844334F429F5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:banking_party_management:2.7.0:*:*:*:*:*:*:*",
"matchCriteriaId": "C542DC5E-6657-4178-9C69-46FD3C187D56",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:banking_platform:2.6.2:*:*:*:*:*:*:*",
"matchCriteriaId": "132CE62A-FBFC-4001-81EC-35D81F73AF48",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:coherence:12.2.1.4.0:*:*:*:*:*:*:*",
"matchCriteriaId": "2FF57C7A-92C9-4D71-A7B1-CC9DEFAA8193",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:coherence:14.1.1.0.0:*:*:*:*:*:*:*",
"matchCriteriaId": "5FA64A1D-34F9-4441-857A-25C165E6DBB6",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:1.11.0:*:*:*:*:*:*:*",
"matchCriteriaId": "10323322-F6C0-4EA7-9344-736F7A80AA5F",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_network_slice_selection_function:1.8.0:*:*:*:*:*:*:*",
"matchCriteriaId": "3AA09838-BF13-46AC-BB97-A69F48B73A8A",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.15.0:*:*:*:*:*:*:*",
"matchCriteriaId": "B4367D9B-BF81-47AD-A840-AC46317C774D",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_security_edge_protection_proxy:1.7.0:*:*:*:*:*:*:*",
"matchCriteriaId": "BD4349FE-EEF8-489A-8ABF-5FCD55EC6DE0",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_cloud_native_core_unified_data_repository:1.15.0:*:*:*:*:*:*:*",
"matchCriteriaId": "C6EAA723-2A23-4151-930B-86ACF9CC1C0C",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_design_studio:7.4.2:*:*:*:*:*:*:*",
"matchCriteriaId": "A67AA54B-258D-4D09-9ACB-4085E0B3E585",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:communications_instant_messaging_server:8.1:*:*:*:*:*:*:*",
"matchCriteriaId": "47CE14F1-7E98-4C3B-A817-C54273F23464",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:helidon:1.4.10:*:*:*:*:*:*:*",
"matchCriteriaId": "4E7626D2-D9FF-416A-9581-852CED0D8C24",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:helidon:2.4.0:*:*:*:*:*:*:*",
"matchCriteriaId": "99344A5D-F4B7-49B4-9AE6-0E2FB3874EA5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:*",
"matchCriteriaId": "D9DB4A14-2EF5-4B54-95D2-75E6CF9AA0A9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.59:*:*:*:*:*:*:*",
"matchCriteriaId": "C8AF00C6-B97F-414D-A8DF-057E6BFD8597",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
},
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
"matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
"matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers \u0026 clients. Netty prior to version 4.1.71.Final skips control chars when they are present at the beginning / end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to \"sanitize\" header names before it forward these to another remote system when used as proxy. This remote system can\u0027t see the invalid usage anymore, and therefore does not do the validation itself. Users should upgrade to version 4.1.71.Final."
},
{
"lang": "es",
"value": "Netty es un marco de trabajo de aplicaciones de red as\u00edncronas impulsadas por eventos para el desarrollo r\u00e1pido de servidores y clientes de protocolo de alto rendimiento mantenibles. Netty antes de la versi\u00f3n 4.1.71.Final omite los caracteres de control cuando est\u00e1n presentes al principio/fin del nombre de la cabecera. En su lugar, deber\u00eda fallar r\u00e1pidamente ya que estos no est\u00e1n permitidos por la especificaci\u00f3n y podr\u00edan llevar a un contrabando de peticiones HTTP. No hacer la validaci\u00f3n podr\u00eda causar que netty \"sanee\" los nombres de las cabeceras antes de reenviarlas a otro sistema remoto cuando se usa como proxy. Este sistema remoto ya no puede ver el uso inv\u00e1lido, y por lo tanto no hace la validaci\u00f3n por s\u00ed mismo. Los usuarios deben actualizar a la versi\u00f3n 4.1.71.Final"
}
],
"id": "CVE-2021-43797",
"lastModified": "2026-10-08T22:17:12.930",
"metrics": {
"cvssMetricV2": [
{
"acInsufInfo": false,
"baseSeverity": "MEDIUM",
"cvssData": {
"accessComplexity": "MEDIUM",
"accessVector": "NETWORK",
"authentication": "NONE",
"availabilityImpact": "NONE",
"baseScore": 4.3,
"confidentialityImpact": "NONE",
"integrityImpact": "PARTIAL",
"vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
"version": "2.0"
},
"exploitabilityScore": 8.6,
"impactScore": 2.9,
"obtainAllPrivilege": false,
"obtainOtherPrivilege": false,
"obtainUserPrivilege": false,
"source": "nvd@nist.gov",
"type": "Primary",
"userInteractionRequired": true
}
],
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"version": "3.1"
},
"exploitabilityScore": 2.8,
"impactScore": 3.6,
"source": "security-advisories@github.com",
"type": "Secondary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"version": "3.1"
},
"exploitabilityScore": 2.8,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-43797",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-10-08T21:08:01.062250Z",
"version": "2.0.3"
}
}
]
},
"published": "2021-12-09T19:15:07.960",
"references": [
{
"source": "security-advisories@github.com",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"source": "security-advisories@github.com",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"source": "security-advisories@github.com",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"source": "security-advisories@github.com",
"tags": [
"Third Party Advisory"
],
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"source": "security-advisories@github.com",
"tags": [
"Third Party Advisory"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
},
{
"source": "security-advisories@github.com",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"source": "security-advisories@github.com",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
}
],
"sourceIdentifier": "security-advisories@github.com",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-444"
}
],
"source": "security-advisories@github.com",
"type": "Secondary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-444"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-11-02T01:19:11+00:00",
"cve": "CVE-2021-43797",
"id": "CVE-2021-43797",
"initial_release_date": "2021-12-09T00:00:00+00:00",
"product_status:fixed": "103",
"product_status:known_affected": "15",
"product_status:known_not_affected": "5877",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "netty: control chars in header names may lead to HTTP request smuggling",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-43797.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-10-11T02:04:52Z",
"cve": "CVE-2021-43797",
"id": "CVE-2021-43797",
"initial_release_date": "2023-02-15T03:36:48Z",
"product_status:known_not_affected": "3",
"product_status:recommended": "53",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2021-43797",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-43797.json",
"version": "14"
},
"vulnrichment": {
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-04T04:03:08.898Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"tags": [
"x_transferred"
],
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"tags": [
"x_transferred"
],
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"tags": [
"x_transferred"
],
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"name": "[debian-lts-announce] 20230111 [SECURITY] [DLA 3268-1] netty security update",
"tags": [
"mailing-list",
"x_transferred"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"name": "DSA-5316",
"tags": [
"vendor-advisory",
"x_transferred"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-43797",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-10-08T21:08:01.062250Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-10-08T21:08:01.831Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "netty",
"vendor": "netty",
"versions": [
{
"status": "affected",
"version": "\u003c= 4.1.7.0.Final"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers \u0026 clients. Netty prior to version 4.1.71.Final skips control chars when they are present at the beginning / end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to \"sanitize\" header names before it forward these to another remote system when used as proxy. This remote system can\u0027t see the invalid usage anymore, and therefore does not do the validation itself. Users should upgrade to version 4.1.71.Final."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-444",
"description": "CWE-444: Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request Smuggling\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2023-01-12T00:00:00.000Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"url": "https://github.com/netty/netty/security/advisories/GHSA-wx5j-54mm-rqqq"
},
{
"url": "https://github.com/netty/netty/commit/07aa6b5938a8b6ed7a6586e066400e2643897323"
},
{
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"url": "https://security.netapp.com/advisory/ntap-20220107-0003/"
},
{
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"name": "[debian-lts-announce] 20230111 [SECURITY] [DLA 3268-1] netty security update",
"tags": [
"mailing-list"
],
"url": "https://lists.debian.org/debian-lts-announce/2023/01/msg00008.html"
},
{
"name": "DSA-5316",
"tags": [
"vendor-advisory"
],
"url": "https://www.debian.org/security/2023/dsa-5316"
}
],
"source": {
"advisory": "GHSA-wx5j-54mm-rqqq",
"discovery": "UNKNOWN"
},
"title": "HTTP fails to validate against control chars in header names which may lead to HTTP request smuggling"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2021-43797",
"datePublished": "2021-12-09T00:00:00.000Z",
"dateReserved": "2021-11-16T00:00:00.000Z",
"dateUpdated": "2026-10-08T21:13:54.692Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.
Loading timeline…
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.