5.3

CVE-2023-51766: debian debian_linux

CVSS: 5.3v3.1MediumModified
AliasesUBUNTU-CVE-2023-51766USN-6611-1DEBIAN-CVE-2023-51766
Published 24-12-2023Last modified 04-11-2025
Open JSON

Vulnerability summary

CVE-2023-51766 is a medium (CVSS 5.3) vulnerability in debian debian_linux. EPSS estimates a 1.10% chance of exploitation in the next 30 days, higher than 65.1% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (NVD)
EPSS score
1.10%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 2 · Related 4
OPENSUSE-SU-2024:0007-1USN-8382-1CGA-329F-XRJ8-7FRGCGA-4J25-M35P-95P5

Timeline

  1. 24-12-2023
    PublishedVulnerability first disclosed.
  2. 04-11-2025
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

1.10%

Chance of exploitation in the next 30 days

Percentile

65%

Versus all other CVEs

30-day change

0.00 pp

From 1.10% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.10%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (youtube.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Debian2 products
  • exim4< 4.97-3 | < 4.94.2-7+deb11u2 | < 4.96-15+deb12u4 | < 4.92-8+deb10u9
  • debian_linuxEOL10.0
Fedoraproject2 products
Chainguard1 product
  • exim< 4.97.1-r0
Exim1 product
Opensuse1 product
  • exim&distro=openSUSE Tumbleweed< 4.97.1-1.1
Ubuntu1 product
  • exim4< 4.82-3ubuntu2.4+esm9 | < 4.86.2-2ubuntu2.6+esm6 | < 4.90.1-1ubuntu1.10+esm3 | < 4.93-13ubuntu1.10 | < 4.95-4ubuntu2.5
Wolfi1 product
  • exim< 4.97.1-r0

7 vendors · 9 products

References

30 links
Show all 30 references