CVE-2021-28692

{"id": "CVE-2021-28692", "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 5.6, "accessVector": "LOCAL", "vectorString": "AV:L/AC:L/Au:N/C:P/I:N/A:C", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "LOW", "availabilityImpact": "COMPLETE", "confidentialityImpact": "PARTIAL"}, "acInsufInfo": false, "impactScore": 7.8, "baseSeverity": "MEDIUM", "obtainAllPrivilege": false, "exploitabilityScore": 3.9, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.1, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 1.8}]}, "published": "2021-06-30T11:15:08.087", "references": [{"url": "https://security.gentoo.org/glsa/202107-30", "tags": ["Mitigation", "Third Party Advisory"], "source": "security@xen.org"}, {"url": "https://xenbits.xenproject.org/xsa/advisory-373.txt", "tags": ["Vendor Advisory"], "source": "security@xen.org"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-269"}]}], "descriptions": [{"lang": "en", "value": "inappropriate x86 IOMMU timeout detection / handling IOMMUs process commands issued to them in parallel with the operation of the CPU(s) issuing such commands. In the current implementation in Xen, asynchronous notification of the completion of such commands is not used. Instead, the issuing CPU spin-waits for the completion of the most recently issued command(s). Some of these waiting loops try to apply a timeout to fail overly-slow commands. The course of action upon a perceived timeout actually being detected is inappropriate: - on Intel hardware guests which did not originally cause the timeout may be marked as crashed, - on AMD hardware higher layer callers would not be notified of the issue, making them continue as if the IOMMU operation succeeded."}, {"lang": "es", "value": "Una detecci\u00f3n/manipulaci\u00f3n inapropiada del tiempo de espera de la IOMMU x86 Las IOMMUs procesan los comandos emitidos a ellas en paralelo con la operaci\u00f3n de la(s) CPU(s) que emiten dichos comandos. En la implementaci\u00f3n actual en Xen, la notificaci\u00f3n as\u00edncrona de la finalizaci\u00f3n de dichos comandos no es usada. En su lugar, la CPU emisora espera la finalizaci\u00f3n de la(s) \u00faltima(s) orden(es) emitida(s). Algunos de estos bucles de espera intentan aplicar un tiempo de espera para crear un fallo en los comandos demasiado lentos. El curso de acci\u00f3n cuando se detecta un tiempo de espera es inapropiado: - en el hardware de Intel los hu\u00e9spedes que no causaron originalmente el tiempo de espera pueden ser marcados como bloqueados, - en el hardware de AMD los llamadores de la capa superior no ser\u00edan notificados del problema, haci\u00e9ndolos continuar como si la operaci\u00f3n de IOMMU tuviera \u00e9xito"}], "lastModified": "2021-07-12T14:53:51.553", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "70FF936F-CF3F-4124-AF44-DAFE2D227F11", "versionStartIncluding": "3.2.0"}], "operator": "OR"}]}], "sourceIdentifier": "security@xen.org"}