CVE-2026-44390

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Unbound 1.25.1 contains a patch with a fix that increments the compression counter regardless of the compression tree lookup. This is a complement fix to CVE-2024-8508."}, {"lang": "es", "value": "NLnet Labs Unbound hasta e incluyendo la versi\u00f3n 1.25.0 tiene una vulnerabilidad al manejar respuestas con RRsets muy grandes para los cuales Unbound necesita realizar compresi\u00f3n de nombres. Respuestas maliciosas de upstream con RRsets muy grandes con registros que no comparten un sufijo por encima de la ra\u00edz pueden causar que Unbound dedique un tiempo considerable a aplicar compresi\u00f3n de nombres a las respuestas de downstream. Esto puede llevar a un rendimiento degradado y eventualmente a una denegaci\u00f3n de servicio en ataques bien orquestados. Un adversario puede explotar la vulnerabilidad consultando a Unbound por el contenido especialmente dise\u00f1ado de una zona maliciosa con RRsets muy grandes. Antes de que Unbound responda a la consulta, intentar\u00e1 aplicar la compresi\u00f3n de nombres, que era una operaci\u00f3n ilimitada que pod\u00eda bloquear la CPU hasta que el paquete completo estuviera listo. Se introdujo un l\u00edmite de compresi\u00f3n en la versi\u00f3n 1.21.1 para esto, pero no tuvo en cuenta el caso en que los registros no compartieran ning\u00fan sufijo por encima de la ra\u00edz. Eso hace que Unbound siga una ruta de c\u00f3digo diferente debido al fallo en la b\u00fasqueda del \u00e1rbol de compresi\u00f3n y, finalmente, no incremente el contador de compresi\u00f3n para esas operaciones. Unbound 1.25.1 contiene un parche con una correcci\u00f3n que incrementa el contador de compresi\u00f3n independientemente de la b\u00fasqueda del \u00e1rbol de compresi\u00f3n. Esta es una correcci\u00f3n complementaria para CVE-2024-8508."}], "id": "CVE-2026-44390", "lastModified": "2026-09-01T13:19:32.737", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "nvd@nist.gov", "type": "Primary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 6.9, "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": "NONE", "providerUrgency": "AMBER", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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:Amber", "version": "4.0", "vulnAvailabilityImpact": "LOW", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "sep@nlnetlabs.nl", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-44390", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-20T12:55:48.767374Z", "version": "2.0.3"}}]}, "published": "2026-05-20T10:16:28.183", "references": [{"source": "sep@nlnetlabs.nl", "tags": ["Mitigation", "Vendor Advisory"], "url": "https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-44390.txt"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:24013"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:36320"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:36777"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/errata/RHSA-2026:37282"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://access.redhat.com/security/cve/CVE-2026-44390"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2480130"}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44390.json"}], "sourceIdentifier": "sep@nlnetlabs.nl", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-407"}], "source": "sep@nlnetlabs.nl", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-1050"}], "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.25.1)"}}], "enrichment": {"confidence": 97.0, "confidence_source": "matching", "scores": [{"score": 97.0, "source": "matching"}]}, "original": {"product": "Unbound", "source": "cna", "vendor": "NLnet Labs"}, "product": "unbound", "vendor": "nlnetlabs"}], "created": "2026-05-20T11:30:26.138056+00:00", "updated": "2026-08-13T23:45:16.809233+00:00", "vendors": ["nlnetlabs", "nlnetlabs$PRODUCT$unbound"]}