CVE-2023-51766
exim4 - security update
5.3
MEDIUM
CVSS 3.1
EPSS 1.6%
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.
How to fix CVE-2023-51766
To remediate CVE-2023-51766, upgrade the affected package to a fixed version below.
- —upgrade to 4.94.2-7+deb11u2 or later
- —upgrade to 4.92-8+deb10u9 or later
- —upgrade to 4.94.2-7+deb11u2 or later
Is CVE-2023-51766 being exploited?
Low — EPSS is 1.6%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 4.94.2-7+deb11u2
- from 0, < 4.92-8+deb10u9
- from 0, < 4.94.2-7+deb11u2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |