CVE-2023-51766

Published Dec 24, 2023

Last updated 6 months ago

CVSS medium 5.3
SMTP

Overview

Description
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.
Source
cve@mitre.org
NVD status
Modified
Products
exim, extra_packages_for_enterprise_linux, fedora, debian_linux

Risk scores

CVSS 3.1

Type
Primary
Base score
5.3
Impact score
1.4
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-345

Social media

Hype score
Not currently trending

Configurations

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References

Sources include official advisories and independent security research.