CVE Vulnerabilities

CVE-2020-35680

NULL Pointer Dereference

Published: Dec 24, 2020 | Modified: Nov 07, 2023
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM

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.

Weakness

A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

Affected Software

Name Vendor Start Version End Version
Opensmtpd Opensmtpd * 6.8.0 (excluding)
Opensmtpd Opensmtpd 6.8.0 (including) 6.8.0 (including)
Opensmtpd Opensmtpd 6.8.0-patch1-rc1 (including) 6.8.0-patch1-rc1 (including)
Opensmtpd Ubuntu devel *
Opensmtpd Ubuntu esm-apps/focal *
Opensmtpd Ubuntu esm-apps/jammy *
Opensmtpd Ubuntu esm-apps/noble *
Opensmtpd Ubuntu focal *
Opensmtpd Ubuntu groovy *
Opensmtpd Ubuntu hirsute *
Opensmtpd Ubuntu impish *
Opensmtpd Ubuntu jammy *
Opensmtpd Ubuntu kinetic *
Opensmtpd Ubuntu lunar *
Opensmtpd Ubuntu mantic *
Opensmtpd Ubuntu noble *
Opensmtpd Ubuntu oracular *
Opensmtpd Ubuntu trusty *

Potential Mitigations

References