ubuntu-cve-2026-48840
Vulnerability from osv_ubuntu
Published
2026-05-29 14:00
Modified
2026-06-04 00:17
Summary
Details

Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.

Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.86.2-2ubuntu2.6+esm9"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.86.2-2ubuntu2.6+esm9"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.86.2-2ubuntu2.6+esm9"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.86.2-2ubuntu2.6+esm9"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.86.2-2ubuntu2.6+esm9"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.86.2-2ubuntu2.6+esm9"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.86.2-2ubuntu2.6+esm9?arch=source\u0026distro=esm-infra-legacy/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.86.2-2ubuntu2.6+esm9"
            }
          ],
          "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",
        "4.86.2-2ubuntu2.6+esm7",
        "4.86.2-2ubuntu2.6+esm8"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.90.1-1ubuntu1.10+esm6"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.90.1-1ubuntu1.10+esm6"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.90.1-1ubuntu1.10+esm6"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.90.1-1ubuntu1.10+esm6"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.90.1-1ubuntu1.10+esm6"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.90.1-1ubuntu1.10+esm6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.90.1-1ubuntu1.10+esm6?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.90.1-1ubuntu1.10+esm6"
            }
          ],
          "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",
        "4.90.1-1ubuntu1.10+esm4",
        "4.90.1-1ubuntu1.10+esm5"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.93-13ubuntu1.12+esm1"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.93-13ubuntu1.12+esm1"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.93-13ubuntu1.12+esm1"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.93-13ubuntu1.12+esm1"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.93-13ubuntu1.12+esm1"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.93-13ubuntu1.12+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.93-13ubuntu1.12+esm1?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.93-13ubuntu1.12+esm1"
            }
          ],
          "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",
        "4.93-13ubuntu1.11",
        "4.93-13ubuntu1.12"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.95-4ubuntu2.9"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.95-4ubuntu2.9"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.95-4ubuntu2.9"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.95-4ubuntu2.9"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.95-4ubuntu2.9"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.95-4ubuntu2.9"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.95-4ubuntu2.9?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.95-4ubuntu2.9"
            }
          ],
          "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"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.97-4ubuntu4.6"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.97-4ubuntu4.6"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.97-4ubuntu4.6"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.97-4ubuntu4.6"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.97-4ubuntu4.6"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.97-4ubuntu4.6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.97-4ubuntu4.6?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.97-4ubuntu4.6"
            }
          ],
          "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"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.98.2-1ubuntu2.3"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.98.2-1ubuntu2.3"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.98.2-1ubuntu2.3"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.98.2-1ubuntu2.3"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.98.2-1ubuntu2.3"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.98.2-1ubuntu2.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.98.2-1ubuntu2.3?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.98.2-1ubuntu2.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.98.1-1ubuntu2",
        "4.98.2-1ubuntu1",
        "4.98.2-1ubuntu2",
        "4.98.2-1ubuntu2.1",
        "4.98.2-1ubuntu2.2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "exim4",
            "binary_version": "4.99.1-1ubuntu1.3"
          },
          {
            "binary_name": "exim4-base",
            "binary_version": "4.99.1-1ubuntu1.3"
          },
          {
            "binary_name": "exim4-config",
            "binary_version": "4.99.1-1ubuntu1.3"
          },
          {
            "binary_name": "exim4-daemon-heavy",
            "binary_version": "4.99.1-1ubuntu1.3"
          },
          {
            "binary_name": "exim4-daemon-light",
            "binary_version": "4.99.1-1ubuntu1.3"
          },
          {
            "binary_name": "eximon4",
            "binary_version": "4.99.1-1ubuntu1.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "exim4",
        "purl": "pkg:deb/ubuntu/exim4@4.99.1-1ubuntu1.3?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.99.1-1ubuntu1.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.98.2-1ubuntu2",
        "4.99-4ubuntu1",
        "4.99.1-1ubuntu1",
        "4.99.1-1ubuntu1.1",
        "4.99.1-1ubuntu1.2"
      ]
    }
  ],
  "aliases": [],
  "details": "Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.",
  "id": "UBUNTU-CVE-2026-48840",
  "modified": "2026-06-04T00:17:51Z",
  "published": "2026-05-29T14:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-48840"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-48840"
    },
    {
      "type": "REPORT",
      "url": "https://www.exim.org/static/doc/security/EXIM-Security-2026-05-19.1/EXIM-Security-2026-05-19.1.txt"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8353-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8382-1"
    }
  ],
  "related": [
    "USN-8353-1",
    "USN-8382-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "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"
    }
  ],
  "upstream": [
    "CVE-2026-48840"
  ]
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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