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.
CVSS Details
- CVSS 3.1 Base Score: 9.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade opensmtpdUpgrade opensmtpd-extras | Jan 5, 2021 | Feb 25, 2020 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Feb 25, 2020 |
| Debian | — | Upgrade opensmtpd | Feb 28, 2020 | Feb 25, 2020 |
| Freebsd | — | Upgrade opensmtpd | Dec 10, 2025 | Feb 24, 2020 |
| Ubuntu | — | Upgrade opensmtpd (Ubuntu Pro)Upgrade opensmtpd | Mar 3, 2020 | Feb 24, 2020 |
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