All vulnerabilities

Servers and applications

CVE-2020-28024

Exim 4 before 4.94.2 allows Buffer Underwrite that may result in unauthenticated remote attackers executing arbitrary commands, because smtp_ungetc was only intended to push back characters, but can actually push back non-character error codes such as EOF.

Severity
Critical 9.8
Published
6 May 2021
Last changed
17 Jun 2026
Added to UpHeron
1 Nov 2026
Fixed in
4.94.2
Sources
NVD

Affected software

SoftwareAffected versions
EximServers and applications · cpe:a:exim:exim
  • From 4.00 before 4.94.2

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2020-28024
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2020-28024