CVE-2026-44638

{
  "id": "CVE-2026-44638",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-14T20:17:08.983",
  "lastModified": "2026-10-26T14:10:00.130",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From  to 1.8.7-r1, a wrong NULL check after an allocation call in sixel_decode_raw and sixel_decode causes a NULL pointer dereference whenever the allocation fails. The check tests the address of the output parameter (always non-NULL) instead of the value the malloc returned. On allocation failure, the function continues and writes through a NULL pointer, crashing the process. This is a denial of service against any caller of these public APIs that hits a low-memory condition. This vulnerability is fixed in 1.8.7-r2."
    },
    {
      "lang": "es",
      "value": "libsixel es una implementación de codificador/decodificador SIXEL derivada de sixel de kmiya. Desde hasta 1.8.7-r1, una comprobación de NULL incorrecta después de una llamada de asignación en sixel_decode_raw y sixel_decode causa una desreferencia de puntero NULL siempre que la asignación falla. La comprobación prueba la dirección del parámetro de salida (siempre no-NULL) en lugar del valor que malloc devolvió. En caso de fallo de asignación, la función continúa y escribe a través de un puntero NULL, colapsando el proceso. Esto es una denegación de servicio contra cualquier llamador de estas API públicas que alcanza una condición de poca memoria. Esta vulnerabilidad está corregida en 1.8.7-r2."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "saitoha",
          "product": "libsixel",
          "versions": [
            {
              "version": ">= 1.0.0, < 1.8.7-r2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
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          "baseScore": 2.5,
          "baseSeverity": "LOW",
          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
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          "timestamp": "2026-05-15T14:17:38.241135Z",
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  "references": [
    {
      "url": "https://github.com/saitoha/libsixel/security/advisories/GHSA-wpx3-h5g8-qr3w",
      "source": "[email protected]",
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