CVE-2026-103436

Estado: AplazadaBaja (3.7)—

apcupsd through 3.14.14 discloses uninitialized stack memory in getupsvar() in src/cgi/upsfetch.c (used by upsstats.cgi, multimon.cgi, and upsfstats.cgi. On the single-field path, when the matched STATUS line has fewer than three whitespace-separated tokens, sscanf("%*s %*s %s", answer) performs no assignment but the function returns success, and thus the caller prints the uninitialized destination buffer into the HTTP response.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Puntuación base: 3.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.29%
Percentil entre todas las CVEs puntuadas: 20
Fecha de la puntuación: 6/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access75 %
Impacto principalT1005 Data from Local Systemcollection70 %

Aplicación web expuesta (CGI) que mediante solicitud remota sin autenticación devuelve datos de memoria no inicializada en respuesta HTTP; CWE-457 (uninitialized variable) causa fuga de información.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic Application Isolation and Sandboxing

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Apcupsd — Apcupsd^AI

CWE

CWE-457

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-103436",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-103436",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-02T16:20:15.422577Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "cve@mitre.org",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 3.7,
          "attackVector": "NETWORK",
          "baseSeverity": "LOW",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
        },
        "impactScore": 1.4,
        "exploitabilityScore": 2.2
      }
    ]
  },
  "affected": [
    {
      "source": "cve@mitre.org",
      "affectedData": [
        {
          "vendor": "apcupsd",
          "modules": [
            "apcupsd-cgi (upsstats.cgi",
            "multimon.cgi",
            "upsfstats.cgi)"
          ],
          "product": "apcupsd",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "versionType": "semver",
              "lessThanOrEqual": "3.14.14"
            }
          ],
          "programFiles": [
            "src/cgi/upsfetch.c"
          ],
          "defaultStatus": "unknown",
          "programRoutines": [
            {
              "name": "getupsvar"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-09-30T16:17:09.700",
  "references": [
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2493140",
      "source": "cve@mitre.org"
    },
    {
      "url": "https://github.com/therealbstern/apcupsd/blob/224d19d5faa508d04267f6135fe53d50800550de/src/cgi/upsfetch.c#L240",
      "source": "cve@mitre.org"
    },
    {
      "url": "https://sourceforge.net/projects/apcupsd/",
      "source": "cve@mitre.org"
    }
  ],
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "cve@mitre.org",
      "description": [
        {
          "lang": "en",
          "value": "CWE-457"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "apcupsd through 3.14.14 discloses uninitialized stack memory in getupsvar() in src/cgi/upsfetch.c (used by upsstats.cgi, multimon.cgi, and upsfstats.cgi. On the single-field path, when the matched STATUS line has fewer than three whitespace-separated tokens, sscanf(\"%*s %*s %s\", answer) performs no assignment but the function returns success, and thus the caller prints the uninitialized destination buffer into the HTTP response."
    }
  ],
  "lastModified": "2026-10-02T17:17:02.550",
  "sourceIdentifier": "cve@mitre.org"
}