Exim up to 4.97 E-Mail Message protection mechanism

Summaryinfo

A vulnerability marked as problematic has been reported in Exim up to 4.97. This issue affects some unknown processing of the component E-Mail Message Handler. The manipulation leads to protection mechanism. This vulnerability is referenced as CVE-2023-51766. Remote exploitation of the attack is possible. No exploit is available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in Exim up to 4.97 (Mail Server Software) and classified as problematic. This issue affects an unknown code of the component E-Mail Message Handler. The manipulation with an unknown input leads to a protection mechanism vulnerability. Using CWE to declare the problem leads to CWE-693. The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. Impacted is integrity. The summary by CVE is:

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.

The weakness was published 12/24/2023. The advisory is shared at sec-consult.com. The identification of this vulnerability is CVE-2023-51766 since 12/24/2023. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 214479 (Debian dla-3708 : exim4 - security update), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the databases at Tenable (214479) and CERT Bund (WID-SEC-2026-3076). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• SUSE openSUSE
• Open Source Dovecot

Productinfo

Type

• Mail Server Software

Name

• Exim

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28
• 4.29
• 4.30
• 4.31
• 4.32
• 4.33
• 4.34
• 4.35
• 4.36
• 4.37
• 4.38
• 4.39
• 4.40
• 4.41
• 4.42
• 4.43
• 4.44
• 4.45
• 4.46
• 4.47
• 4.48
• 4.49
• 4.50
• 4.51
• 4.52
• 4.53
• 4.54
• 4.55
• 4.56
• 4.57
• 4.58
• 4.59
• 4.60
• 4.61
• 4.62
• 4.63
• 4.64
• 4.65
• 4.66
• 4.67
• 4.68
• 4.69
• 4.70
• 4.71
• 4.72
• 4.73
• 4.74
• 4.75
• 4.76
• 4.77
• 4.78
• 4.79
• 4.80
• 4.81
• 4.82
• 4.83
• 4.84
• 4.85
• 4.86
• 4.87
• 4.88
• 4.89
• 4.90
• 4.91
• 4.92
• 4.93
• 4.94
• 4.95
• 4.96
• 4.97

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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