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CVE-2026-56109

Full vulnerability record from the local CVENow database.

Description

The Advanced Linux Sound Architecture (ALSA) library before 1.2.16.1 contains a double-free vulnerability in parse_def() in src/conf.c that allows attackers to corrupt memory by supplying maliciously crafted ALSA configuration text. When parsing nested compound or array configuration blocks, parse_def() fails to check return values before continuing, causing snd_config_delete() to be called twice on the same already-freed node, resulting in a NULL-pointer write or invalid memory read.

Severity
HIGH
CVSS score
7.0 (v4.0)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-06-22 18:16:48.557000
Last modified
2026-10-25 23:10:00.167000
View original CVE JSON
{
  "id": "CVE-2026-56109",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-22T18:16:48.557",
  "lastModified": "2026-10-25T23:10:00.167",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Advanced Linux Sound Architecture (ALSA) library before 1.2.16.1 contains a double-free vulnerability in parse_def() in src/conf.c that allows attackers to corrupt memory by supplying maliciously crafted ALSA configuration text. When parsing nested compound or array configuration blocks, parse_def() fails to check return values before continuing, causing snd_config_delete() to be called twice on the same already-freed node, resulting in a NULL-pointer write or invalid memory read."
    },
    {
      "lang": "es",
      "value": "La biblioteca Advanced Linux Sound Architecture (ALSA) anterior a 1.2.16.1 contiene una vulnerabilidad de doble liberación en parse_def() en src/conf.c que permite a los atacantes corromper la memoria al proporcionar texto de configuración de ALSA creado maliciosamente. Al analizar bloques de configuración anidados compuestos o de matriz, parse_def() no verifica los valores de retorno antes de continuar, lo que provoca que snd_config_delete() se llame dos veces en el mismo nodo ya liberado, lo que resulta en una escritura de puntero NULL o una lectura de memoria no válida."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "alsa-project",
          "product": "alsa-lib",
          "defaultStatus": "affected",
          "repo": "https://github.com/alsa-project/alsa-lib",
          "packageURL": "pkg:github/alsa-project/alsa-lib",
          "versions": [
            {
              "version": "0",
              "lessThan": "1.2.16.1",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/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:X",
          "baseScore": 7.0,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "LOW",
          "vulnAvailabilityImpact": "HIGH",
          "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"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 4.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-22T17:29:11.617397Z",
          "id": "CVE-2026-56109",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-415"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/alsa-project/alsa-lib/commit/536dd6f8affdf5197c12a63a71c92a70b2833cc0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/alsa-project/alsa-lib/releases/tag/v1.2.16.1",
      "source": "[email protected]"
    },
    {
      "url": "https://lore.kernel.org/alsa-devel/CAGt8pqBU0p2voB+qHxWGcNJrKHAcBhAyHUUBPLBN-Yj_SiV6MQ@mail.gmail.com/",
      "source": "[email protected]"
    },
    {
      "url": "https://www.vulncheck.com/advisories/alsa-library-double-free-via-parse-def-in-conf-c",
      "source": "[email protected]"
    }
  ]
}