CVE-2020-35680

high

Description

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.

References

https://github.com/openbsd/src/commit/6c3220444ed06b5796dedfd53a0f4becd903c0d1

https://www.mail-archive.com/[email protected]/msg05188.html

https://poolp.org/posts/2020-12-24/december-2020-opensmtpd-6.8.0p1-released-fixed-several-bugs-proposed-several-diffs-book-is-on-github/

https://lists.fedoraproject.org/archives/list/[email protected]/message/5LKTFBQCHGMVPR4IZWHQIYAPM5J3LN3J/

https://lists.fedoraproject.org/archives/list/[email protected]/message/TYAYXRV2DM5K4RU7RHCDZSA2UF6VCTRC/

https://security.gentoo.org/glsa/202105-12

Details

Source: MITRE

Published: 2020-12-24

Updated: 2021-05-26

Type: CWE-476

Risk Information

CVSS v2

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

CVSS v3

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