PT-2020-17390 · Openbsd · Opensmtpd

Published 2020-12-24 · Updated 2022-09-02 · CVE-2020-35680

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions OpenSMTPD versions prior to 6.8.0p1

Description The issue allows remote attackers to cause a denial of service, resulting in a daemon crash, via a crafted pattern of client activity. This occurs because the filter state machine does not properly maintain the I/O channel between the SMTP engine and the filters layer in certain configurations.

Recommendations For versions prior to 6.8.0p1, update to version 6.8.0p1 or later to resolve the issue. As a temporary workaround, consider restricting access to the smtpd/lka filter.c module to minimize the risk of exploitation.

Fix

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

CVE-2020-35680

Affected Products

Opensmtpd

References · 20

• https://github.com/openbsd/src/commit/6c3220444ed06b5796dedfd53a0f4becd903c0d1 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2020-35680 · Vendor Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TYAYXRV2DM5K4RU7RHCDZSA2UF6VCTRC · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2020-35680 · Security Note
• https://ubuntu.com/security/CVE-2020-35680 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2020-35680 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2020-35680 · Vendor Advisory
• https://security.gentoo.org/glsa/202105-12 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2020-35680 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2020-35680 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2020-35680 · Vendor Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LKTFBQCHGMVPR4IZWHQIYAPM5J3LN3J · Vendor Advisory
• https://mail-archive.com/[e-mail]/msg05188.html · Note
• https://mail-archive.com/misc%40opensmtpd.org/msg05188.html · Note
• https://t.me/cvenotify/35620 · Telegram Post