CVE-2020-8794 EXPLOIT
9.8
CRITICAL · CVSS 3.1 · EPSS 88.9% (pctl 100)
Patch early
A public exploit exists.
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.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 88.9% — more likely to be exploited than 100% of all CVEs |
| Weakness | CWE-125 |
| On CISA KEV | no |
| Public exploit | yes |
| Published | 2020-02-25 |
| Last modified | 2026-06-17 |
Affected (4)
| Vendor | Product |
|---|---|
| canonical | ubuntu linux |
| debian | debian linux |
| fedoraproject | fedora |
| opensmtpd | opensmtpd |
Public exploits
| Source | Title | Date |
|---|---|---|
| exploit-db | OpenSMTPD - OOB Read Local Privilege Escalation (Metasploit) | 2020-03-09 |
| exploit-db | OpenSMTPD < 6.6.3p1 - Local Privilege Escalation + Remote Code Execution | 2020-02-26 |
References
- http://packetstormsecurity.com/files/156633/OpenSMTPD-Out-Of-Bounds-Read-Local-Privilege-Escalation.html
- http://seclists.org/fulldisclosure/2020/Feb/32
- http://www.openwall.com/lists/oss-security/2020/02/26/1
- http://www.openwall.com/lists/oss-security/2020/03/01/1
- http://www.openwall.com/lists/oss-security/2020/03/01/2
- http://www.openwall.com/lists/oss-security/2021/05/04/7
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPH4QU4DNVHA7ACFXMYFCEP5PSXXPN4E/
- https://usn.ubuntu.com/4294-1/
- https://www.debian.org/security/2020/dsa-4634
- https://www.openbsd.org/security.html
- https://www.openwall.com/lists/oss-security/2020/02/24/5
- http://packetstormsecurity.com/files/156633/OpenSMTPD-Out-Of-Bounds-Read-Local-Privilege-Escalation.html
- http://seclists.org/fulldisclosure/2020/Feb/32
- http://www.openwall.com/lists/oss-security/2020/02/26/1
- http://www.openwall.com/lists/oss-security/2020/03/01/1
- http://www.openwall.com/lists/oss-security/2020/03/01/2
- http://www.openwall.com/lists/oss-security/2021/05/04/7
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPH4QU4DNVHA7ACFXMYFCEP5PSXXPN4E/
- https://usn.ubuntu.com/4294-1/
- https://www.debian.org/security/2020/dsa-4634
→ the Explorer · watch your stack · NVD