CVE-2020-8794

Public Exploit

Description

OpenSMTPD before 6.6.4 allows remote code execution because of an out-of-bounds read in mta_io in mta_session.c for multi-line replies. Although this vulnerability affects the client side of OpenSMTPD, it is possible to attack a server because the server code launches the client code during bounce handling.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 86.79% Top 5%
Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory ubuntu.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.openbsd.org/security.html third party advisory
https://www.openwall.com/lists/oss-security/2020/02/24/5 mailing list exploit third party advisory
http://www.openwall.com/lists/oss-security/2020/02/26/1 mailing list exploit third party advisory
https://www.debian.org/security/2020/dsa-4634 third party advisory vendor advisory
http://seclists.org/fulldisclosure/2020/Feb/32 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2020/03/01/1 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2020/03/01/2 third party advisory mailing list
http://packetstormsecurity.com/files/156633/OpenSMTPD-Out-Of-Bounds-Read-Local-Privilege-Escalation.html exploit vdb entry third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPH4QU4DNVHA7ACFXMYFCEP5PSXXPN4E/ vendor advisory
https://usn.ubuntu.com/4294-1/ third party advisory patch vendor advisory
http://www.openwall.com/lists/oss-security/2021/05/04/7 mailing list exploit third party advisory

Frequently Asked Questions

What is the severity of CVE-2020-8794?
CVE-2020-8794 has been scored as a critical severity vulnerability.
How to fix CVE-2020-8794?
To fix CVE-2020-8794, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-8794 being actively exploited in the wild?
It is possible that CVE-2020-8794 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~87% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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