GHSA-W6WW-869J-CGM6

Vulnerability from github – Published: 2023-12-24 06:30 – Updated: 2025-11-04 21:30
VLAI
Details

Exim through 4.97 allows SMTP smuggling in certain configurations. Remote attackers can use a published exploitation technique to inject e-mail messages that appear to originate from the Exim server, allowing bypass of an SPF protection mechanism. This occurs because Exim supports . but some other popular e-mail servers do not.

Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2023-51766"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-345"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-12-24T06:15:07Z",
    "severity": "MODERATE"
  },
  "details": "Exim through 4.97 allows SMTP smuggling in certain configurations. Remote attackers can use a published exploitation technique to inject e-mail messages that appear to originate from the Exim server, allowing bypass of an SPF protection mechanism. This occurs because Exim supports \u003cLF\u003e.\u003cCR\u003e\u003cLF\u003e but some other popular e-mail servers do not.",
  "id": "GHSA-w6ww-869j-cgm6",
  "modified": "2025-11-04T21:30:53Z",
  "published": "2023-12-24T06:30:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-51766"
    },
    {
      "type": "WEB",
      "url": "https://www.youtube.com/watch?v=V8KPV96g1To"
    },
    {
      "type": "WEB",
      "url": "https://www.openwall.com/lists/oss-security/2023/12/23/2"
    },
    {
      "type": "WEB",
      "url": "https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide"
    },
    {
      "type": "WEB",
      "url": "https://lwn.net/Articles/956533"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QPDWHJPABVJCXDSNELSSVTIVAJU2MDUQ"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ORN7OKEQPPBKUHYRQ6LR5PSNBQVDHAWB"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QPDWHJPABVJCXDSNELSSVTIVAJU2MDUQ"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORN7OKEQPPBKUHYRQ6LR5PSNBQVDHAWB"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2024/01/msg00002.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Exim/exim/blob/master/doc/doc-txt/cve-2023-51766"
    },
    {
      "type": "WEB",
      "url": "https://git.exim.org/exim.git/commit/cf1376206284f2a4f11e32d931d4aade34c206c5"
    },
    {
      "type": "WEB",
      "url": "https://git.exim.org/exim.git/commit/5bb786d5ad568a88d50d15452aacc8404047e5ca"
    },
    {
      "type": "WEB",
      "url": "https://fahrplan.events.ccc.de/congress/2023/fahrplan/events/11782.html"
    },
    {
      "type": "WEB",
      "url": "https://exim.org/static/doc/security/CVE-2023-51766.txt"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2255852"
    },
    {
      "type": "WEB",
      "url": "https://bugs.exim.org/show_bug.cgi?id=3063"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2023/12/24/1"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2023/12/25/1"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2023/12/29/2"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2024/01/01/1"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2024/01/01/2"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2024/01/01/3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}



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