vulnerability
Exim: Heap buffer underflow in smtp_ungetc() (CVE-2020-28024)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:L/Au:N/C:P/I:P/A:P) | May 6, 2021 | May 13, 2021 | Apr 7, 2026 |
Severity
8
CVSS
(AV:N/AC:L/Au:N/C:P/I:P/A:P)
Published
May 6, 2021
Added
May 13, 2021
Modified
Apr 7, 2026
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.
Solution
exim-upgrade-4_94_2
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