CVE-2025-2486

// CVE-2025-2486 PoC - UEFI Shell Secure Boot Bypass // This PoC demonstrates the concept of UEFI Shell access in Secure Boot environment // Note: Actual exploitation requires physical/local access to the target system /* Attack Prerequisites: 1. Physical access to target system 2. System booted with vulnerable Ubuntu edk2 firmware 3. Secure Boot must be enabled Attack Steps: 1. Interrupt normal boot process 2. Access UEFI Boot Manager or Shell 3. Execute arbitrary commands or load unsigned executables Detection Method: - Monitor UEFI variables for unexpected Shell access - Check for unsigned executables in boot paths - Review Secure Boot policy violations in system logs Example detection command: cat /sys/firmware/efi/efivars/SecureBoot-* 2>/dev/null Mitigation: - Update to Ubuntu edk2 version 2024.05-2ubuntu0.3 or 2024.02-2ubuntu0.3 - Ensure UEFI Shell is disabled in firmware configuration - Enable and configure Secure Boot properly */

{"cve": {"id": "CVE-2025-2486", "sourceIdentifier": "[email protected]", "published": "2025-11-26T18:15:48.357", "lastModified": "2025-12-19T16:31:04.217", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "The Ubuntu edk2 UEFI firmware packages accidentally allowed the UEFI Shell to be accessed in Secure Boot environments, possibly allowing bypass of Secure Boot constraints. Versions 2024.05-2ubuntu0.3 and 2024.02-2ubuntu0.3 disable the Shell. Some previous versions inserted a secure-boot-based decision to continue running inside the Shell itself, which is believed to be sufficient to enforce Secure Boot restrictions. This is an additional repair on top of the incomplete fix for CVE-2023-48733."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:H/SI:H/SA:H/E:U/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", "baseScore": 3.7, "baseSeverity": "LOW", "attackVector": "LOCAL", "attackComplexity": "HIGH", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "ACTIVE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "HIGH", "subAvailabilityImpact": "HIGH", "exploitMaturity": "UNREPORTED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.0, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-489"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:tianocore:edk2:202402*:*:*:*:*:*:*:*", "matchCriteriaId": "AEEAC129-5714-416C-B689-09707A561451"}, {"vulnerable": true, "criteria": "cpe:2.3:a:tianocore:edk2:202405:*:*:*:*:*:*:*", "matchCriteriaId": "67420046-C0C1-4B20-9B5F-A1F4ED477798"}]}]}], "references": [{"url": "https://bugs.launchpad.net/ubuntu/+source/edk2/+bug/2101797", "source": "[email protected]", "tags": ["Third Party Advisory", "Patch"]}]}}