CVE-2026-31838

{"id": "CVE-2026-31838", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.9, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "LOW", "vulnConfidentialityImpact": "LOW", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "published": "2026-03-10T22:16:21.870", "references": [{"url": "https://github.com/istio/istio/commit/004fd6921314a8e2293fd195d91645dcbbff0aa1", "source": "security-advisories@github.com"}, {"url": "https://github.com/istio/istio/security/advisories/GHSA-974c-2wxh-g4ww", "tags": ["Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-863"}]}], "descriptions": [{"lang": "en", "value": "Istio is an open platform to connect, manage, and secure microservices. Prior to 1.29.1, 1.28.5, and 1.27.8, a vulnerability in Envoy RBAC header matching could allow authorization policy bypass when policies rely on HTTP headers that may contain multiple values. An attacker could craft requests with multiple header values in a way that causes Envoy to evaluate the header differently than intended, potentially bypassing authorization checks. This may allow unauthorized requests to reach protected services when policies depend on such header-based matching conditions. This vulnerability is fixed in 1.29.1, 1.28.5, and 1.27.8."}, {"lang": "es", "value": "Istio es una plataforma abierta para conectar, gestionar y proteger microservicios. Antes de 1.29.1, 1.28.5 y 1.27.8, una vulnerabilidad en la coincidencia de encabezados RBAC de Envoy podr\u00eda permitir la omisi\u00f3n de la pol\u00edtica de autorizaci\u00f3n cuando las pol\u00edticas dependen de encabezados HTTP que pueden contener m\u00faltiples valores. Un atacante podr\u00eda elaborar solicitudes con m\u00faltiples valores de encabezado de una manera que hace que Envoy eval\u00fae el encabezado de forma diferente a lo previsto, potencialmente omitiendo las comprobaciones de autorizaci\u00f3n. Esto podr\u00eda permitir que solicitudes no autorizadas lleguen a servicios protegidos cuando las pol\u00edticas dependen de tales condiciones de coincidencia basadas en encabezados. Esta vulnerabilidad est\u00e1 corregida en 1.29.1, 1.28.5 y 1.27.8."}], "lastModified": "2026-04-07T03:16:07.900", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DE1D1FE4-AFED-401D-9806-64A2BCD3E4B4", "versionEndExcluding": "1.27.8"}, {"criteria": "cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B739C51C-21B8-4697-90E0-89D74035D191", "versionEndExcluding": "1.28.5", "versionStartIncluding": "1.28.0"}, {"criteria": "cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4E81CE4C-D040-4F85-AAFE-4CEA4906E14A", "versionEndExcluding": "1.29.1", "versionStartIncluding": "1.29.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}