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CVE-1999-0159

Status: ModifiedLow (3.5)—
Severity3.5Low · CVSS 3.1
Exploitation probability1.10 %higher than 65% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

Attackers can crash a Cisco IOS router or device, provided they can get to an interactive prompt (such as a login). This applies to some IOS 9.x, 10.x, and 11.x releases.

CVSS

Base score
3.5
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
1.10 %
Percentile among all scored CVEs
65
Score date
10/23/2026

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).

Affected technologies (1)

Cisco — IOS

CWEs

References

Show 2 references

Raw JSON (NVD)

Show
{
  "id": "CVE-1999-0159",
  "cveTags": [],
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          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2025-08-27T18:38:07.688027Z"
        }
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          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "NONE"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
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        "cvssData": {
          "scope": "UNCHANGED",
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          "baseSeverity": "LOW",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L",
          "integrityImpact": "NONE",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "LOW",
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    ]
  },
  "affected": [
    {
      "source": "cve@mitre.org",
      "affectedData": [
        {
          "vendor": "n/a",
          "product": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
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        }
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    }
  ],
  "published": "1998-08-12T04:00:00.000",
  "references": [
    {
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0159",
      "source": "cve@mitre.org"
    },
    {
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0159",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
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    },
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      "type": "Secondary",
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      "description": [
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          "lang": "en",
          "value": "CWE-400"
        }
      ]
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  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Attackers can crash a Cisco IOS router or device, provided they can get to an interactive prompt (such as a login).  This applies to some IOS 9.x, 10.x, and 11.x releases."
    }
  ],
  "lastModified": "2026-06-16T21:47:43.593",
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}