CVE-2011-4408

Status: ModifiedMedium (6.8)—

The Single Sign On Client (ubuntu-sso-client) for Ubuntu 11.04 and 11.10 does not properly validate SSL certificates when using HTTPS, which allows remote attackers to spoof a server and modify or read sensitive data via a man-in-the-middle (MITM) attack.

CVSS

Version: 2.0
Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P
Base score: 6.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.24%
Percentile among all scored CVEs: 69
Score date: 10/14/2026

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)

Canonical — Ubuntu Linux

CWEs

NVD-CWE-Other

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2011-4408",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 6.8,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 6.4,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 8.6,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ]
  },
  "affected": [
    {
      "source": "security@ubuntu.com",
      "affectedData": [
        {
          "vendor": "n/a",
          "product": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ]
    }
  ],
  "published": "2012-06-16T00:55:05.547",
  "references": [
    {
      "url": "http://osvdb.org/82747",
      "source": "security@ubuntu.com"
    },
    {
      "url": "http://secunia.com/advisories/49448",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@ubuntu.com"
    },
    {
      "url": "http://www.securityfocus.com/bid/53829",
      "source": "security@ubuntu.com"
    },
    {
      "url": "http://www.ubuntu.com/usn/USN-1464-1",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security@ubuntu.com"
    },
    {
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/76112",
      "source": "security@ubuntu.com"
    },
    {
      "url": "http://osvdb.org/82747",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://secunia.com/advisories/49448",
      "tags": [
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      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.securityfocus.com/bid/53829",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "http://www.ubuntu.com/usn/USN-1464-1",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/76112",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-Other"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Single Sign On Client (ubuntu-sso-client) for Ubuntu 11.04 and 11.10 does not properly validate SSL certificates when using HTTPS, which allows remote attackers to spoof a server and modify or read sensitive data via a man-in-the-middle (MITM) attack."
    },
    {
      "lang": "es",
      "value": "El cliente de Single Sign On (ubuntu-sso-client) de Ubuntu 11.04 y 11.10 no valida apropiadamente los certificados cuando se utiliza HTTPS, lo que permite a atacantes remotos suplantar un servidor y modificar o leer información confidencial a través de un ataque de man-in-the-middle (MITM)."
    }
  ],
  "lastModified": "2026-06-16T23:34:52.883",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:canonical:ubuntu_linux:11.04:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "EF49D26F-142E-468B-87C1-BABEA445255C"
            },
            {
              "criteria": "cpe:2.3:o:canonical:ubuntu_linux:11.10:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "E4174F4F-149E-41A6-BBCC-D01114C05F38"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security@ubuntu.com"
}