CVE-2026-11835

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{"affected": [{"affectedData": [{"collectionURL": "https://github.com/chipsalliance/caliptra-sw", "defaultStatus": "unaffected", "modules": ["UpdateResetFlow::run()"], "packageName": "Core ROM", "product": "Core ROM", "vendor": "Caliptra", "versions": [{"lessThanOrEqual": "2.1.1", "status": "affected", "version": "2.1.0", "versionType": "semver"}, {"status": "unaffected", "version": "2.1.2", "versionType": "semver"}]}], "source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554"}], "cveTags": [], "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."}, {"lang": "es", "value": "Vulnerabilidad de tiempo de verificaci\u00f3n y tiempo de uso (TOCTOU) combinada con la falta de validaci\u00f3n de entrada en la ROM del n\u00facleo de Caliptra (UpdateResetFlow::run()) en modo de subsistema permite a un atacante local comprometido eludir silenciosamente el arranque seguro al proporcionar una direcci\u00f3n de preparaci\u00f3n AXI que no se valida contra la direcci\u00f3n base del \u00e1rea de preparaci\u00f3n externa (SS_EXTERNAL_STAGING_AREA_BASE_ADDR) configurada por correa, lo que permite que el firmware sea modificado entre la verificaci\u00f3n y la carga en el ICCM. La atestaci\u00f3n contin\u00faa informando el resumen de imagen verificado originalmente, enmascarando el compromiso. La explotaci\u00f3n requiere un firmware de MCU comprometido con acceso de administrador AXI a SRAM desprotegida accesible por Caliptra.\n\nEste problema afecta a la ROM del n\u00facleo: 2.1.0 a 2.1.1."}], "id": "CVE-2026-11835", "lastModified": "2026-10-23T23:10:00.157", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "attackVector": "LOCAL", "availabilityRequirement": "NOT_DEFINED", "baseScore": 5.7, "baseSeverity": "MEDIUM", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "HIGH", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-11835", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-08-04T19:21:52.034967Z", "version": "2.0.3"}}]}, "published": "2026-08-04T00:16:40.047", "references": [{"source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554", "url": "https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-49mm-5gq5-v97f"}], "sourceIdentifier": "b01ddd03-5ef6-483b-b2c5-acba77f1a554", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-367"}], "source": "b01ddd03-5ef6-483b-b2c5-acba77f1a554", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2.1.0,2.1.1]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "2.1.2"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "Core ROM", "source": "cna", "vendor": "Caliptra"}, "product": "core_rom", "vendor": "caliptra"}], "created": "2026-08-04T21:15:03.482060+00:00", "updated": "2026-08-05T10:21:20.245473+00:00", "vendors": ["caliptra", "caliptra$PRODUCT$core_rom"]}