« Back to list

CVE-2020-3477

Status: ModifiedMedium (5.5)—

A vulnerability in the CLI parser of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, local attacker to access files from the flash: filesystem. The vulnerability is due to insufficient application of restrictions during the execution of a specific command. An attacker could exploit this vulnerability by using a specific command at the command line. A successful exploit could allow the attacker to obtain read-only access to files that are located on the flash: filesystem that otherwise might not have been accessible.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Source: official MITRE CTID mapping (CVE → ATT&CK).

🛡️ ATT&CK mitigations that cover these techniques

Application Developer GuidanceActive Directory ConfigurationUser TrainingUser Account ManagementPrivileged Account ManagementPassword Policies

Affected technologies (1)

Cisco — IOS

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2020-3477",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2020-3477",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2024-11-13T17:23:19.644914Z"
        }
      }
    ],
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 2.1,
          "accessVector": "LOCAL",
          "vectorString": "AV:L/AC:L/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "LOW",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 3.9,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV30": [
      {
        "type": "Secondary",
        "source": "psirt@cisco.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.0",
          "baseScore": 5.5,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 1.8
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.5,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "psirt@cisco.com",
      "affectedData": [
        {
          "vendor": "Cisco",
          "product": "Cisco IOS",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ]
    }
  ],
  "published": "2020-09-24T18:15:19.917",
  "references": [
    {
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-info-disclosure-V4BmJBNF",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "psirt@cisco.com"
    },
    {
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-info-disclosure-V4BmJBNF",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "psirt@cisco.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        }
      ]
    },
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-863"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the CLI parser of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, local attacker to access files from the flash: filesystem. The vulnerability is due to insufficient application of restrictions during the execution of a specific command. An attacker could exploit this vulnerability by using a specific command at the command line. A successful exploit could allow the attacker to obtain read-only access to files that are located on the flash: filesystem that otherwise might not have been accessible."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en el analizador de la CLI de Cisco IOS Software y Cisco IOS XE Software, podría permitir a un atacante local autenticado acceder a archivos desde la flash: filesystem. La vulnerabilidad es debido a una aplicación insuficiente de restricciones durante la ejecución de un comando específico. Un atacante podría explotar esta vulnerabilidad mediante el uso de un comando específico en la línea de comandos. Una explotación con éxito podría permitir al atacante conseguir acceso de solo lectura a archivos que están ubicados en la flash: filesystem que de otro modo no podría haber sido accesible."
    }
  ],
  "lastModified": "2026-06-17T03:18:22.767",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:cisco:ios:16.3.11:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "AAA3919B-5067-4451-9109-3A52C380BCAA"
            }
          ],
          "operator": "OR"
        },
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:h:cisco:2610xm:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "9E9B9F16-2D70-4109-999F-6A10D82DD68D"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2611xm:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "F77581A8-F334-445E-978C-D57F5135830B"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2612:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "E22D6ADA-DC1D-4916-9039-D0970727DE46"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2620xm:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "0CF86B51-A53D-4B3A-89B6-BFF3D40397B6"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2621xm:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "83F5E77F-E325-472B-AD80-98B2C2DBF0AB"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2650xm:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "E997D0D5-5436-4E39-8032-F6EA5DA45340"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2651xm:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "EF18B92D-D063-4D98-8D59-5AF02443DC4E"
            },
            {
              "criteria": "cpe:2.3:h:cisco:2691:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "5F4063DC-7653-4777-B012-C49CCDD0E0B5"
            }
          ],
          "operator": "OR"
        }
      ],
      "operator": "AND"
    }
  ],
  "sourceIdentifier": "psirt@cisco.com"
}