OpenSMTPD up to 6.6.3 mta_session.c out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k0.00

A vulnerability was found in OpenSMTPD up to 6.6.3. It has been declared as critical. Affected by this vulnerability is an unknown code block of the file mta_session.c. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was published 02/25/2020. This vulnerability is known as CVE-2020-8794 since 02/07/2020. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details and also a public exploit are known.

A public exploit has been developed by Qualys Corporation in C and been published 1 days after the advisory. It is possible to download the exploit at exploit-db.com. It is declared as highly functional.

Upgrading to version 6.6.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Exploit-DB (48140). Similar entry is available at VDB-150504.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Highly functional
Author: Qualys Corporation
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Upgrade: OpenSMTPD 6.6.4

Timelineinfo

02/07/2020 🔍
02/25/2020 +18 days 🔍
02/26/2020 +1 days 🔍
02/26/2020 +0 days 🔍
04/02/2024 +1497 days 🔍

Sourcesinfo

Advisory: 156633
Status: Not defined

CVE: CVE-2020-8794 (🔍)
scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 02/26/2020 07:59
Updated: 04/02/2024 22:10
Changes: 02/26/2020 07:59 (36), 03/02/2020 14:37 (24), 04/02/2024 21:55 (22), 04/02/2024 22:10 (2)
Complete: 🔍
Committer: misc
Cache ID: 18:F91:103

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