CVE-2020-28024 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28024-UNGET.txt

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8