9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
0.975 High
EPSS
Percentile
100.0%
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.
Recent assessments:
wvu-r7 at February 26, 2020 1:04am UTC reported:
> If such a remote
server is controlled by an attacker (either because it is malicious or
compromised, or because of a man-in-the-middle, DNS, or BGP attack β
SMTP is not TLS-encrypted by default), then the attacker can execute
arbitrary shell commands on the vulnerable OpenSMTPD installation.
This seems to be the primary limitation for exploitation. You canβt just give OpenSMTPD an IP address. You need to control an MX host or relay, so a little more setup is required. Contrast this with CVE-2020-7247, which is directly exploitable against the server.
Assessed Attacker Value: 0
Assessed Attacker Value: 0Assessed Attacker Value: 0
packetstormsecurity.com/files/156633/OpenSMTPD-Out-Of-Bounds-Read-Local-Privilege-Escalation.html
seclists.org/fulldisclosure/2020/Feb/32
www.openwall.com/lists/oss-security/2020/02/26/1
www.openwall.com/lists/oss-security/2020/03/01/1
www.openwall.com/lists/oss-security/2020/03/01/2
www.openwall.com/lists/oss-security/2021/05/04/7
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-8794
lists.fedoraproject.org/archives/list/[email protected]/message/OPH4QU4DNVHA7ACFXMYFCEP5PSXXPN4E
lists.fedoraproject.org/archives/list/[email protected]/message/OPH4QU4DNVHA7ACFXMYFCEP5PSXXPN4E/
usn.ubuntu.com/4294-1
usn.ubuntu.com/4294-1/
www.debian.org/security/2020/dsa-4634
www.openbsd.org/security.html
www.openwall.com/lists/oss-security/2020/02/24/5
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
0.975 High
EPSS
Percentile
100.0%