ubuntu-cve-2021-38371
Vulnerability from osv_ubuntu
Published
2021-08-10 15:15
Modified
2026-04-22 07:40
Summary
Details

The STARTTLS feature in Exim through 4.94.2 allows response injection (buffering) during MTA SMTP sending.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.82-3ubuntu2.4+esm8"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.82-3ubuntu2.4+esm8"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.82-3ubuntu2.4+esm8"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.82-3ubuntu2.4+esm8"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.82-3ubuntu2.4+esm8"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.82-3ubuntu2.4+esm8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.82-3ubuntu2.4+esm8?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.82-3ubuntu2.4+esm8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.80-7ubuntu3",
        "4.80-7ubuntu4",
        "4.80-9ubuntu1",
        "4.80-9ubuntu2",
        "4.82-3ubuntu1",
        "4.82-3ubuntu2",
        "4.82-3ubuntu2.1",
        "4.82-3ubuntu2.2",
        "4.82-3ubuntu2.3",
        "4.82-3ubuntu2.4",
        "4.82-3ubuntu2.4+esm1",
        "4.82-3ubuntu2.4+esm2",
        "4.82-3ubuntu2.4+esm3",
        "4.82-3ubuntu2.4+esm4",
        "4.82-3ubuntu2.4+esm6",
        "4.82-3ubuntu2.4+esm7"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.86.2-2ubuntu2.6+esm7"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.86.2-2ubuntu2.6+esm7"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.86.2-2ubuntu2.6+esm7"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.86.2-2ubuntu2.6+esm7"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.86.2-2ubuntu2.6+esm7"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.86.2-2ubuntu2.6+esm7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.86.2-2ubuntu2.6+esm7?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.86.2-2ubuntu2.6+esm7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.86-3ubuntu1",
        "4.86-7ubuntu1",
        "4.86-7ubuntu2",
        "4.86-7ubuntu3",
        "4.86.2-2ubuntu1",
        "4.86.2-2ubuntu2",
        "4.86.2-2ubuntu2.1",
        "4.86.2-2ubuntu2.2",
        "4.86.2-2ubuntu2.3",
        "4.86.2-2ubuntu2.4",
        "4.86.2-2ubuntu2.5",
        "4.86.2-2ubuntu2.6",
        "4.86.2-2ubuntu2.6+esm1",
        "4.86.2-2ubuntu2.6+esm2",
        "4.86.2-2ubuntu2.6+esm4",
        "4.86.2-2ubuntu2.6+esm5",
        "4.86.2-2ubuntu2.6+esm6"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.90.1-1ubuntu1.10+esm4"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.90.1-1ubuntu1.10+esm4"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.90.1-1ubuntu1.10+esm4"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.90.1-1ubuntu1.10+esm4"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.90.1-1ubuntu1.10+esm4"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.90.1-1ubuntu1.10+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.90.1-1ubuntu1.10+esm4?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.90.1-1ubuntu1.10+esm4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.89-5ubuntu1",
        "4.89-9ubuntu1",
        "4.89-9ubuntu2",
        "4.89-9ubuntu3",
        "4.89-9ubuntu4",
        "4.90.1-1ubuntu1",
        "4.90.1-1ubuntu1.1",
        "4.90.1-1ubuntu1.2",
        "4.90.1-1ubuntu1.3",
        "4.90.1-1ubuntu1.4",
        "4.90.1-1ubuntu1.5",
        "4.90.1-1ubuntu1.8",
        "4.90.1-1ubuntu1.9",
        "4.90.1-1ubuntu1.10",
        "4.90.1-1ubuntu1.10+esm1",
        "4.90.1-1ubuntu1.10+esm2",
        "4.90.1-1ubuntu1.10+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.93-13ubuntu1.11"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.93-13ubuntu1.11"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.93-13ubuntu1.11"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.93-13ubuntu1.11"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.93-13ubuntu1.11"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.93-13ubuntu1.11"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.93-13ubuntu1.11?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.93-13ubuntu1.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.92.1-1ubuntu3",
        "4.92.1-1ubuntu4",
        "4.93~RC2-1ubuntu1",
        "4.93-9ubuntu1",
        "4.93-11ubuntu1",
        "4.93-12ubuntu1",
        "4.93-13ubuntu1",
        "4.93-13ubuntu1.1",
        "4.93-13ubuntu1.5",
        "4.93-13ubuntu1.6",
        "4.93-13ubuntu1.7",
        "4.93-13ubuntu1.8",
        "4.93-13ubuntu1.9",
        "4.93-13ubuntu1.10"
      ]
    }
  ],
  "aliases": [],
  "details": "The STARTTLS feature in Exim through 4.94.2 allows response injection (buffering) during MTA SMTP sending.",
  "id": "UBUNTU-CVE-2021-38371",
  "modified": "2026-04-22T07:40:08Z",
  "published": "2021-08-10T15:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-38371"
    },
    {
      "type": "REPORT",
      "url": "https://nostarttls.secvuln.info"
    },
    {
      "type": "REPORT",
      "url": "https://www.exim.org/static/doc/security/CVE-2021-38371.txt"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-38371"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6881-1"
    }
  ],
  "related": [
    "USN-6881-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-38371"
  ]
}



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