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    "cveMetadata": {
        "cveId": "CVE-2026-6420",
        "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "state": "PUBLISHED",
        "assignerShortName": "redhat",
        "dateReserved": "2026-04-16T06:03:46.656Z",
        "datePublished": "2026-05-06T10:19:39.121Z",
        "dateUpdated": "2026-08-26T16:35:19.571Z"
    },
    "containers": {
        "cna": {
            "title": "Keylime: keylime: security bypass due to hardcoded tpm quote nonce",
            "metrics": [
                {
                    "other": {
                        "content": {
                            "value": "Moderate",
                            "namespace": "https://access.redhat.com/security/updates/classification/"
                        },
                        "type": "Red Hat severity rating"
                    }
                },
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "LOCAL",
                        "availabilityImpact": "LOW",
                        "baseScore": 6.3,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "HIGH",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L",
                        "version": "3.1"
                    },
                    "format": "CVSS"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "A flaw was found in Keylime. An attacker with root access on an enrolled monitored machine, where the Keylime agent runs, can exploit a vulnerability in the Keylime verifier. The verifier uses a hardcoded challenge nonce for Trusted Platform Module (TPM) quote attestation instead of a cryptographically random value. This allows the attacker to stockpile valid TPM quotes and replay them to evade detection after compromising the system. This issue affects only the push model deployment."
                }
            ],
            "affected": [
                {
                    "versions": [
                        {
                            "status": "affected",
                            "version": "7.14.0",
                            "lessThan": "7.14.2",
                            "versionType": "semver"
                        }
                    ],
                    "packageName": "keylime",
                    "collectionURL": "https://github.com/keylime/keylime",
                    "defaultStatus": "unaffected"
                },
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Enterprise Linux 10",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "keylime",
                    "defaultStatus": "affected",
                    "versions": [
                        {
                            "version": "0:7.14.1-5.el10_2.1",
                            "lessThan": "*",
                            "versionType": "rpm",
                            "status": "unaffected"
                        }
                    ],
                    "cpes": [
                        "cpe:/o:redhat:enterprise_linux:10.2"
                    ]
                },
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Enterprise Linux 9",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "keylime",
                    "defaultStatus": "affected",
                    "cpes": [
                        "cpe:/o:redhat:enterprise_linux:9"
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://access.redhat.com/errata/RHSA-2026:28582",
                    "name": "RHSA-2026:28582",
                    "tags": [
                        "vendor-advisory",
                        "x_refsource_REDHAT"
                    ]
                },
                {
                    "url": "https://access.redhat.com/security/cve/CVE-2026-6420",
                    "tags": [
                        "vdb-entry",
                        "x_refsource_REDHAT"
                    ]
                },
                {
                    "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2458889",
                    "name": "RHBZ#2458889",
                    "tags": [
                        "issue-tracking",
                        "x_refsource_REDHAT"
                    ]
                }
            ],
            "datePublic": "2026-05-06T10:00:00.000Z",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-1241",
                            "description": "Use of Predictable Algorithm in Random Number Generator",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "x_redhatCweChain": "CWE-1241: Use of Predictable Algorithm in Random Number Generator",
            "workarounds": [
                {
                    "lang": "en",
                    "value": "Primary fix (one-line change in keylime/models/verifier/evidence.py):\nBefore (vulnerable):\ndef generate_challenge(self, bit_length):\n\nself.challenge = Nonce.generate(bit_length)\n self.challenge = bytes.fromhex(\"49beed365aac777dae23564f5ad0ec\")\n\nAfter (fixed):\ndef generate_challenge(self, bit_length):\nself.challenge = Nonce.generate(bit_length)\n\nExisting partial mitigations (already active):\n\n1. TPM clock monotonicity check: limits each quote to one replay.\n2. Push attestation timeout (default 10s): constrains the quote generation window, but TPM throughput allows 50-200 quotes to be stockpiled in that time."
                }
            ],
            "timeline": [
                {
                    "lang": "en",
                    "time": "2026-04-16T06:01:38.993Z",
                    "value": "Reported to Red Hat."
                },
                {
                    "lang": "en",
                    "time": "2026-05-06T10:00:00.000Z",
                    "value": "Made public."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Red Hat would like to thank Keylime developers for reporting this issue."
                }
            ],
            "providerMetadata": {
                "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
                "shortName": "redhat",
                "dateUpdated": "2026-08-26T16:35:19.571Z"
            },
            "x_generator": {
                "engine": "cvelib 1.8.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-05-06T13:54:45.881598Z",
                                "id": "CVE-2026-6420",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
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                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
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                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
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                    "dateUpdated": "2026-05-06T15:24:21.052Z"
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}