{
    "dataType": "CVE_RECORD",
    "cveMetadata": {
        "cveId": "CVE-2026-40395",
        "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "state": "PUBLISHED",
        "assignerShortName": "mitre",
        "dateReserved": "2026-04-12T19:21:08.847Z",
        "datePublished": "2026-04-12T19:21:09.265Z",
        "dateUpdated": "2026-04-13T15:45:30.791Z"
    },
    "containers": {
        "cna": {
            "affected": [
                {
                    "defaultStatus": "unaffected",
                    "product": "Varnish Enterprise",
                    "vendor": "varnish-software",
                    "versions": [
                        {
                            "lessThan": "6.0.16r12",
                            "status": "affected",
                            "version": "6.0.9r5",
                            "versionType": "custom"
                        }
                    ]
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Varnish Enterprise before 6.0.16r12 allows a \"workspace overflow\" denial of service (daemon panic) for shared VCL. The headerplus.write_req0() function from vmod_headerplus updates the underlying req0, which is normally the original read-only request from which req is derived (readable and writable from VCL). This is useful in the active VCL, after amending req, to prepare a refined req0 before switching to a different VCL with the return (vcl(<label>)) action. This is for example how the Varnish Controller operates shared VCL deployments. If the amended req contained too many header fields for req0, this would have resulted in a workspace overflow that would in turn trigger a panic and crash the Varnish Enterprise server. This could be used as a Denial of Service attack vector by malicious clients."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "LOW",
                        "baseScore": 4,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "CHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L",
                        "version": "3.1"
                    },
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ]
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-770",
                            "description": "CWE-770 Allocation of Resources Without Limits or Throttling",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
                "shortName": "mitre",
                "dateUpdated": "2026-04-12T19:33:44.790Z"
            },
            "references": [
                {
                    "url": "https://docs.varnish-software.com/security/VEV00003/"
                }
            ],
            "x_generator": {
                "engine": "CVE-Request-form 0.0.1"
            },
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:varnish-software:varnish_enterprise:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0.9r5",
                                    "versionEndExcluding": "6.0.16r12"
                                }
                            ]
                        }
                    ]
                }
            ]
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-04-13T15:45:24.491498Z",
                                "id": "CVE-2026-40395",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "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": "2026-04-13T15:45:30.791Z"
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