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{"bugzilla": {"description": "Varnish: Varnish Enterprise: Denial of Service via workspace overflow", "id": "2457698", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2457698"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.0", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-770", "details": ["A flaw was found in Varnish Enterprise. A remote attacker can exploit this vulnerability by sending a request with an excessive number of header fields. This can cause a \"workspace overflow\" within the vmod_headerplus module, leading to a daemon panic and crashing the Varnish Enterprise server. This results in a Denial of Service (DoS), making the server unavailable to legitimate users."], "name": "CVE-2026-40395", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "varnish", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "varnish:6/varnish", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "varnish", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-12T19:21:09Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-40395\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-40395\nhttps://docs.varnish-software.com/security/VEV00003/"], "threat_severity": "Moderate"}