USN-8834-1 (UBUNTU-CVE-2026-94054)

Vulnerability from osv_ubuntu – Published: 2026-09-28 12:05 – Updated: 2026-09-28 12:05 – Source website
VLAI
Summary
exim4 vulnerabilities
Details

It was discovered that Exim had an out-of-bounds write when Proxy-Protocol was used with an attacker-controlled proxy. A remote attacker could possibly use this issue to execute arbitrary code. (CVE-2026-94054)

It was discovered that Exim had a use-after-free when certain non-default TLS settings were used with GnuTLS. A remote attacker could possibly use this issue to cause Exim to crash, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-94055)

It was discovered that Exim allowed attackers to read uninitialized data from stack memory when Proxy-Protocol was used with an attacker-controlled proxy. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-94056)

It was discovered that Exim allowed SMTP smuggling via crafted data sent after a rejection during DATA processing. A remote attacker could possibly use this issue to inject arbitrary email messages. (CVE-2026-94057)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-94054",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94056",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94057",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.95-4ubuntu2.12"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.95-4ubuntu2.12"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.95-4ubuntu2.12"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.95-4ubuntu2.12"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.95-4ubuntu2.12"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.95-4ubuntu2.12"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.95-4ubuntu2.12?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.95-4ubuntu2.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.94.2-7ubuntu2",
        "4.95-2ubuntu2",
        "4.95-4ubuntu1",
        "4.95-4ubuntu2",
        "4.95-4ubuntu2.1",
        "4.95-4ubuntu2.2",
        "4.95-4ubuntu2.3",
        "4.95-4ubuntu2.4",
        "4.95-4ubuntu2.5",
        "4.95-4ubuntu2.6",
        "4.95-4ubuntu2.7",
        "4.95-4ubuntu2.8",
        "4.95-4ubuntu2.9",
        "4.95-4ubuntu2.10",
        "4.95-4ubuntu2.11"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-94054",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94056",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94057",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.97-4ubuntu4.8"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.97-4ubuntu4.8"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.97-4ubuntu4.8"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.97-4ubuntu4.8"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.97-4ubuntu4.8"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.97-4ubuntu4.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.97-4ubuntu4.8?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.97-4ubuntu4.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.96-17ubuntu2",
        "4.96-17ubuntu2.1",
        "4.97-3ubuntu1",
        "4.97-4ubuntu1",
        "4.97-4ubuntu3",
        "4.97-4ubuntu4",
        "4.97-4ubuntu4.1",
        "4.97-4ubuntu4.2",
        "4.97-4ubuntu4.3",
        "4.97-4ubuntu4.4",
        "4.97-4ubuntu4.5",
        "4.97-4ubuntu4.6",
        "4.97-4ubuntu4.7"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-94054",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94055",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94056",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-94057",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.99.1-1ubuntu1.5"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.99.1-1ubuntu1.5"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.99.1-1ubuntu1.5"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.99.1-1ubuntu1.5"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.99.1-1ubuntu1.5"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.99.1-1ubuntu1.5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.99.1-1ubuntu1.5?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.99.1-1ubuntu1.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.98.2-1ubuntu2",
        "4.99-4ubuntu1",
        "4.99.1-1ubuntu1",
        "4.99.1-1ubuntu1.1",
        "4.99.1-1ubuntu1.2",
        "4.99.1-1ubuntu1.3",
        "4.99.1-1ubuntu1.4"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that Exim had an out-of-bounds write when\nProxy-Protocol was used with an attacker-controlled proxy. A remote\nattacker could possibly use this issue to execute arbitrary code.\n(CVE-2026-94054)\n\nIt was discovered that Exim had a use-after-free when certain\nnon-default TLS settings were used with GnuTLS. A remote attacker\ncould possibly use this issue to cause Exim to crash, resulting in\na denial of service. This issue only affected Ubuntu 26.04 LTS.\n(CVE-2026-94055)\n\nIt was discovered that Exim allowed attackers to read uninitialized\ndata from stack memory when Proxy-Protocol was used with an\nattacker-controlled proxy. A remote attacker could possibly use this\nissue to obtain sensitive information. (CVE-2026-94056)\n\nIt was discovered that Exim allowed SMTP smuggling via crafted data\nsent after a rejection during DATA processing. A remote attacker\ncould possibly use this issue to inject arbitrary email messages.\n(CVE-2026-94057)",
  "id": "USN-8834-1",
  "modified": "2026-09-28T12:05:13Z",
  "published": "2026-09-28T12:05:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8834-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-94054"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-94055"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-94056"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-94057"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "exim4 vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2026-94054",
    "UBUNTU-CVE-2026-94055",
    "UBUNTU-CVE-2026-94056",
    "UBUNTU-CVE-2026-94057"
  ]
}



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