{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-11835",
        "assignerOrgId": "b01ddd03-5ef6-483b-b2c5-acba77f1a554",
        "state": "PUBLISHED",
        "assignerShortName": "Caliptra",
        "dateReserved": "2026-06-09T23:30:36.611Z",
        "datePublished": "2026-08-04T00:03:23.278Z",
        "dateUpdated": "2026-08-04T21:25:26.656Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "b01ddd03-5ef6-483b-b2c5-acba77f1a554",
                "shortName": "Caliptra",
                "dateUpdated": "2026-08-04T21:25:26.656Z"
            },
            "title": "Caliptra Update-Reset Secure-Boot Bypass via Attacker-Chosen AXI Staging Address (TOCTOU)",
            "datePublic": "2026-08-03T00:00:00.000Z",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-367",
                            "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-20",
                            "description": "CWE-20 Improper Input Validation",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "impacts": [
                {
                    "capecId": "CAPEC-29",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "CAPEC-29 Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Caliptra",
                    "product": "Core ROM",
                    "collectionURL": "https://github.com/chipsalliance/caliptra-sw",
                    "packageName": "Core ROM",
                    "modules": [
                        "UpdateResetFlow::run()"
                    ],
                    "versions": [
                        {
                            "status": "affected",
                            "version": "2.1.0",
                            "lessThanOrEqual": "2.1.1",
                            "versionType": "semver"
                        },
                        {
                            "status": "unaffected",
                            "version": "2.1.2",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Time-of-check time-of-use (TOCTOU) vulnerability combined with missing input validation in Caliptra Core ROM (UpdateResetFlow::run()) in subsystem mode allows a compromised local attacker to silently bypass secure boot by supplying an AXI staging address that is not validated against the strap-configured SS_EXTERNAL_STAGING_AREA_BASE_ADDR, enabling firmware to be modified between verification and loading into ICCM. Attestation continues to report the originally verified image digest, masking the compromise. Exploitation requires a compromised MCU firmware with AXI manager access to unprotected SRAM reachable by Caliptra.\n\nThis issue affects Core ROM: 2.1.0 through 2.1.1.",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": "Time-of-check time-of-use (TOCTOU) vulnerability combined with missing input validation in Caliptra Core ROM (UpdateResetFlow::run()) in subsystem mode allows a compromised local attacker to silently bypass secure boot by supplying an AXI staging address that is not validated against the strap-configured SS_EXTERNAL_STAGING_AREA_BASE_ADDR, enabling firmware to be modified between verification and loading into ICCM. Attestation continues to report the originally verified image digest, masking the compromise. Exploitation requires a compromised MCU firmware with AXI manager access to unprotected SRAM reachable by Caliptra.<p>This issue affects Core ROM: 2.1.0 through 2.1.1.</p>"
                        }
                    ]
                }
            ],
            "tags": [
                "x_open-source"
            ],
            "references": [
                {
                    "url": "https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-49mm-5gq5-v97f"
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ],
                    "cvssV4_0": {
                        "attackVector": "LOCAL",
                        "attackComplexity": "HIGH",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "HIGH",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "LOW",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "valueDensity": "NOT_DEFINED",
                        "vulnerabilityResponseEffort": "NOT_DEFINED",
                        "providerUrgency": "NOT_DEFINED",
                        "version": "4.0",
                        "baseSeverity": "MEDIUM",
                        "baseScore": 5.6,
                        "vectorString": "CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N"
                    }
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Alex Matrosov with Claude, Anthropic",
                    "type": "finder"
                }
            ],
            "source": {
                "discovery": "INTERNAL"
            },
            "x_generator": {
                "engine": "Vulnogram 1.0.2"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-04T19:21:52.034967Z",
                                "id": "CVE-2026-11835",
                                "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": "2026-08-04T19:24:22.359Z"
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    }
}