smtpd/lka_filter.c in OpenSMTPD before 6.8.0p1, in certain configurations, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted pattern of client activity, because the filter state machine does not properly maintain the I/O channel between the SMTP engine and the filters layer.
https://github.com/openbsd/src/commit/6c3220444ed06b5796dedfd53a0f4becd903c0d1
https://www.mail-archive.com/[email protected]/msg05188.html
Source: MITRE
Published: 2020-12-24
Updated: 2021-05-26
Type: CWE-476
Base Score: 5
Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 10
Severity: MEDIUM
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 3.9
Severity: HIGH