CVE-2020-35680: Null Pointer Dereference

Published Dec 24, 2020
·
Updated

smtpd/lkafilter.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.

Affected Software

5 affected components
OpenSMTPD OpenSMTPD<6.8.0
OpenSMTPD OpenSMTPD=6.8.0
OpenSMTPD OpenSMTPD=6.8.0-patch1-rc1
Fedoraproject Fedora=32
Fedoraproject Fedora=33

Event History

Dec 24, 2020
CVE Published
via MITRE·03:53 PM
Data Sourced
via MITRE·03:53 PM
Description
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Frequently Asked Questions

1

What is CVE-2020-35680?

CVE-2020-35680 is a vulnerability in OpenSMTPD before 6.8.0p1 that can allow remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted pattern of client activity.

2

How does CVE-2020-35680 impact OpenSMTPD?

CVE-2020-35680 can cause a denial of service in OpenSMTPD, leading to a crash of the daemon.

3

What is the severity of CVE-2020-35680?

The severity of CVE-2020-35680 is high, with a CVSS score of 7.5.

4

Which versions of OpenSMTPD are affected by CVE-2020-35680?

OpenSMTPD versions before 6.8.0p1 are affected by CVE-2020-35680.

5

How can I fix CVE-2020-35680?

To fix CVE-2020-35680, it is recommended to update to OpenSMTPD 6.8.0p1 or later.

Contact

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