UBUNTU-CVE-2023-51766
- Source
- https://ubuntu.com/security/CVE-2023-51766
- Import Source
- https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-51766.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/UBUNTU-CVE-2023-51766
- Upstream
- Downstream
- Related
- Published
- 2023-12-24T06:15:00Z
- Modified
- 2025-09-08T16:56:37Z
- Severity
-
- 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
- Ubuntu - medium
- Summary
- [none]
- Details
-
Exim before 4.97.1 allows SMTP smuggling in certain PIPELINING/CHUNKING configurations. Remote attackers can use a published exploitation technique to inject e-mail messages with a spoofed MAIL FROM address, allowing bypass of an SPF protection mechanism. This occurs because Exim supports <LF>.<CR><LF> but some other popular e-mail servers do not.
- References
-
- https://ubuntu.com/security/CVE-2023-51766
- https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/
- https://www.openwall.com/lists/oss-security/2023/12/21/6
- https://exim.org/static/doc/security/CVE-2023-51766.txt
- https://git.exim.org/exim.git/commit/cf1376206284f2a4f11e32d931d4aade34c206c5
- https://git.exim.org/exim.git/commit/4596719398f6f2365bed563aafd757a6433ce7b4
- https://git.exim.org/exim.git/commit/5bb786d5ad568a88d50d15452aacc8404047e5ca
- https://ubuntu.com/security/notices/USN-6611-1
- https://www.cve.org/CVERecord?id=CVE-2023-51766
Affected packages
Ubuntu:Pro:14.04:LTS / exim4
Package
- Name
- exim4
- Purl
- pkg:deb/ubuntu/exim4@4.82-3ubuntu2.4+esm8?arch=source&distro=esm-infra-legacy/trusty
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affected
Affected versions
4.*
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
4.82-3ubuntu2.4+esm8
Ecosystem specific
{
"binaries": [
{
"binary_version": "4.82-3ubuntu2.4+esm8",
"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": "exim4-dev"
},
{
"binary_version": "4.82-3ubuntu2.4+esm8",
"binary_name": "eximon4"
}
]
}
Ubuntu:Pro:16.04:LTS / exim4
Package
- Name
- exim4
- Purl
- pkg:deb/ubuntu/exim4@4.86.2-2ubuntu2.6+esm6?arch=source&distro=esm-infra/xenial
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed4.86.2-2ubuntu2.6+esm6
Affected versions
4.*
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
Ecosystem specific
{
"binaries": [
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "exim4"
},
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "exim4-base"
},
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "exim4-config"
},
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "exim4-daemon-heavy"
},
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "exim4-daemon-light"
},
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "exim4-dev"
},
{
"binary_version": "4.86.2-2ubuntu2.6+esm6",
"binary_name": "eximon4"
}
],
"availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"
}
Ubuntu:Pro:18.04:LTS / exim4
Package
- Name
- exim4
- Purl
- pkg:deb/ubuntu/exim4@4.90.1-1ubuntu1.10+esm3?arch=source&distro=esm-infra/bionic
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed4.90.1-1ubuntu1.10+esm3
Affected versions
4.*
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
Ecosystem specific
{
"binaries": [
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "exim4"
},
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "exim4-base"
},
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "exim4-config"
},
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "exim4-daemon-heavy"
},
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "exim4-daemon-light"
},
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "exim4-dev"
},
{
"binary_version": "4.90.1-1ubuntu1.10+esm3",
"binary_name": "eximon4"
}
],
"availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"
}
Ubuntu:20.04:LTS / exim4
Package
- Name
- exim4
- Purl
- pkg:deb/ubuntu/exim4@4.93-13ubuntu1.10?arch=source&distro=focal
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed4.93-13ubuntu1.10
Affected versions
4.*
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
Ecosystem specific
{
"binaries": [
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "exim4"
},
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "exim4-base"
},
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "exim4-config"
},
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "exim4-daemon-heavy"
},
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "exim4-daemon-light"
},
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "exim4-dev"
},
{
"binary_version": "4.93-13ubuntu1.10",
"binary_name": "eximon4"
}
],
"availability": "No subscription required"
}
Ubuntu:22.04:LTS / exim4
Package
- Name
- exim4
- Purl
- pkg:deb/ubuntu/exim4@4.95-4ubuntu2.5?arch=source&distro=jammy
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0Unknown introduced version / All previous versions are affectedFixed4.95-4ubuntu2.5
Affected versions
4.*
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
Ecosystem specific
{
"binaries": [
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "exim4"
},
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "exim4-base"
},
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "exim4-config"
},
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "exim4-daemon-heavy"
},
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "exim4-daemon-light"
},
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "exim4-dev"
},
{
"binary_version": "4.95-4ubuntu2.5",
"binary_name": "eximon4"
}
],
"availability": "No subscription required"
}