{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-77756", "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09", "state": "PUBLISHED", "assignerShortName": "apache", "dateReserved": "2026-08-21T09:55:42.227Z", "datePublished": "2026-09-23T11:18:02.672Z", "dateUpdated": "2026-09-23T11:18:02.672Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09", "shortName": "apache", "dateUpdated": "2026-09-23T11:18:02.672Z"}, "title": "Apache Tomcat: Transfer-Encoding honored for HTTP/1.0 requests", "problemTypes": [{"descriptions": [{"description": "CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')", "lang": "en", "cweId": "CWE-444", "type": "CWE"}]}], "source": {"discovery": "INTERNAL"}, "affected": [{"vendor": "Apache Software Foundation", "product": "Apache Tomcat", "versions": [{"status": "affected", "version": "11.0.0-M1", "lessThanOrEqual": "11.0.25", "versionType": "semver"}, {"status": "affected", "version": "10.1.0-M1", "lessThanOrEqual": "10.1.59", "versionType": "semver"}, {"status": "affected", "version": "9.0.47", "lessThanOrEqual": "9.0.121", "versionType": "semver"}, {"status": "affected", "version": "8.5.67", "lessThanOrEqual": "8.5.100", "versionType": "semver"}, {"status": "unaffected", "version": "0", "lessThanOrEqual": "7.0.109", "versionType": "semver"}], "defaultStatus": "unaffected"}], "descriptions": [{"value": "Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat caused by processing the transfer-encoding header for an HTTP/1.0 request may allow an attacker to cause one request from another user to fail when Tomcat is located behind a reverse proxy.\n\n\n\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.\n\n\n\nThe following versions were EOL at the time the CVE was created but are \nknown to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.\n\n\n\nUsers are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.", "lang": "en", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat caused by processing the transfer-encoding header for an HTTP/1.0 request may allow an attacker to cause one request from another user to fail when Tomcat is located behind a reverse proxy.</p><p>This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.</p><p>The following versions were EOL at the time the CVE was created but are \nknown to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.</p><p>Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.</p>"}]}], "references": [{"url": "https://lists.apache.org/thread/bl5b6rxqh3vb2k9bj2794vhor7o6xl3z", "tags": ["vendor-advisory"]}], "metrics": [{"other": {"type": "Textual description of severity", "content": {"text": "low"}}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "x_generator": {"engine": "Vulnogram 0.2.0"}}}}

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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Apache Tomcat", "vendor": "Apache Software Foundation", "versions": [{"lessThanOrEqual": "11.0.25", "status": "affected", "version": "11.0.0-M1", "versionType": "semver"}, {"lessThanOrEqual": "10.1.59", "status": "affected", "version": "10.1.0-M1", "versionType": "semver"}, {"lessThanOrEqual": "9.0.121", "status": "affected", "version": "9.0.47", "versionType": "semver"}, {"lessThanOrEqual": "8.5.100", "status": "affected", "version": "8.5.67", "versionType": "semver"}, {"lessThanOrEqual": "7.0.109", "status": "unaffected", "version": "0", "versionType": "semver"}]}], "source": "security@apache.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat caused by processing the transfer-encoding header for an HTTP/1.0 request may allow an attacker to cause one request from another user to fail when Tomcat is located behind a reverse proxy.\n\n\n\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.\n\n\n\nThe following versions were EOL at the time the CVE was created but are \nknown to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.\n\n\n\nUsers are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue."}], "id": "CVE-2026-77756", "lastModified": "2026-09-23T12:17:06.663", "metrics": {}, "published": "2026-09-23T12:17:06.663", "references": [{"source": "security@apache.org", "url": "https://lists.apache.org/thread/bl5b6rxqh3vb2k9bj2794vhor7o6xl3z"}], "sourceIdentifier": "security@apache.org", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-444"}], "source": "security@apache.org", "type": "Primary"}]}

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