CVE-2026-40243

Full vulnerability record from the local CVENow database.

Description

Incus is a system container and virtual machine manager. In versions before 7.0.0, broken TLS validation logic in the OVN database connection logic can allow connections to an attacker's OVN database. The OVN client implementations disable Go standard TLS server verification and replace it with custom peer-certificate verification logic. That replacement verifier does not anchor trust in the configured CA certificate. Instead, it constructs the verification root set from certificates supplied by the peer during the handshake, so the configured CA is parsed but not used as the trust anchor for the final verification decision. In OVN-enabled deployments that use these SSL database connection paths, an attacker able to impersonate or intercept the OVN endpoint on the management network can present a rogue self-signed certificate chain, and Incus will accept this certificate as valid. This issue defeats the intended CA-based trust model for OVN database connections and permits endpoint impersonation by an active attacker in a suitable network position. This issue is fixed in version 7.0.0.

Severity

LOW

CVSS score

2.3 (v4.0)

Vulnerability status

Analyzed

Source identifier

[email protected]

Published

2026-05-06 21:16:01.070000

Last modified

2026-10-26 19:10:00.163000

View original CVE JSON

{
  "id": "CVE-2026-40243",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-06T21:16:01.070",
  "lastModified": "2026-10-26T19:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Incus is a system container and virtual machine manager. In versions before 7.0.0, broken TLS validation logic in the OVN database connection logic can allow connections to an attacker's OVN database. The OVN client implementations disable Go standard TLS server verification and replace it with custom peer-certificate verification logic. That replacement verifier does not anchor trust in the configured CA certificate. Instead, it constructs the verification root set from certificates supplied by the peer during the handshake, so the configured CA is parsed but not used as the trust anchor for the final verification decision.\n\nIn OVN-enabled deployments that use these SSL database connection paths, an attacker able to impersonate or intercept the OVN endpoint on the management network can present a rogue self-signed certificate chain, and Incus will accept this certificate as valid. This issue defeats the intended CA-based trust model for OVN database connections and permits endpoint impersonation by an active attacker in a suitable network position. This issue is fixed in version 7.0.0."
    },
    {
      "lang": "es",
      "value": "Incus es un gestor de contenedores de sistema y máquinas virtuales. En versiones anteriores a la 7.0.0, una lógica de validación TLS defectuosa en la lógica de conexión de la base de datos OVN puede permitir conexiones a la base de datos OVN de un atacante. Las implementaciones del cliente OVN deshabilitan la verificación estándar del servidor TLS de Go y la reemplazan con una lógica de verificación de certificado de par personalizada. Ese verificador de reemplazo no ancla la confianza en el certificado de CA configurado. En su lugar, construye el conjunto raíz de verificación a partir de certificados proporcionados por el par durante el handshake, por lo que la CA configurada se analiza pero no se utiliza como ancla de confianza para la decisión de verificación final.\n\nEn despliegues habilitados para OVN que utilizan estas rutas de conexión de base de datos SSL, un atacante capaz de suplantar o interceptar el endpoint OVN en la red de gestión puede presentar una cadena de certificados autofirmados maliciosos, e Incus aceptará este certificado como válido. Este problema anula el modelo de confianza basado en CA previsto para las conexiones de la base de datos OVN y permite la suplantación de endpoints por parte de un atacante activo en una posición de red adecuada. Este problema está solucionado en la versión 7.0.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "lxc",
          "product": "incus",
          "versions": [
            {
              "version": "< 7.0.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
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        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
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          "baseScore": 2.3,
          "baseSeverity": "LOW",
          "attackVector": "ADJACENT",
          "attackComplexity": "HIGH",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "LOW",
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          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "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"
        }
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    ],
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 2.5
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-07T14:02:44.630167Z",
          "id": "CVE-2026-40243",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-295"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "7.0.0",
              "matchCriteriaId": "CF8EBB4B-C1F0-44C5-B063-9CF8EB6E0972"
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        }
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  ],
  "references": [
    {
      "url": "https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_icnb.go",
      "source": "[email protected]",
      "tags": [
        "Product"
      ]
    },
    {
      "url": "https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_icsb.go",
      "source": "[email protected]",
      "tags": [
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    {
      "url": "https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_nb.go",
      "source": "[email protected]",
      "tags": [
        "Product"
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    },
    {
      "url": "https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_sb.go",
      "source": "[email protected]",
      "tags": [
        "Product"
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    },
    {
      "url": "https://github.com/lxc/incus/security/advisories/GHSA-c839-4qxr-j4x3",
      "source": "[email protected]",
      "tags": [
        "Exploit",
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}