CVE-2026-77756

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{"bugzilla": {"description": "tomcat: Apache Tomcat: Request smuggling vulnerability can lead to denial of service", "id": "2539351", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2539351"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-444", "details": ["A flaw was found in Apache Tomcat. This vulnerability, known as HTTP Request/Response Smuggling, occurs when Tomcat processes the transfer-encoding header for an HTTP/1.0 request while operating behind a reverse proxy. A remote attacker could exploit this to cause a denial of service, leading to one user's request failing due to interference from another user's request."], "name": "CVE-2026-77756", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Under investigation", "package_name": "tomcat9", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Under investigation", "package_name": "tomcat6", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Under investigation", "package_name": "pki-deps:10.6/pki-servlet-engine", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Under investigation", "package_name": "pki-servlet-engine", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "hi/tomcat", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "tomcat10", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "tomcat11", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:jboss_enterprise_web_server:5", "fix_state": "Under investigation", "package_name": "jws5-tomcat", "product_name": "Red Hat JBoss Web Server 5"}, {"cpe": "cpe:/a:redhat:jboss_enterprise_web_server:6", "fix_state": "Under investigation", "package_name": "jws6-tomcat", "product_name": "Red Hat JBoss Web Server 6"}, {"cpe": "cpe:/a:redhat:jboss_enterprise_web_server:7", "fix_state": "Under investigation", "package_name": "jws7-tomcat", "product_name": "Red Hat JBoss Web Server 7"}], "public_date": "2026-09-23T11:18:02Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-77756\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-77756\nhttps://lists.apache.org/thread/bl5b6rxqh3vb2k9bj2794vhor7o6xl3z"], "threat_severity": "Moderate"}

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