CVE-2017-16943

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 47.1% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2017-11-25 · updated 2026-06-17
Weakness: CWE-416

Description

The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via vectors involving BDAT commands.

Affected products

Debian Linux: 9.0
Exim: 4.88, 4.89

References

http://openwall.com/lists/oss-security/2017/11/25/1
http://openwall.com/lists/oss-security/2017/11/25/2
http://openwall.com/lists/oss-security/2017/11/25/3
http://www.openwall.com/lists/oss-security/2021/05/04/7
http://www.securitytracker.com/id/1039872
https://bugs.exim.org/show_bug.cgi?id=2199
https://git.exim.org/exim.git/commit/4090d62a4b25782129cc1643596dc2f6e8f63bde
https://git.exim.org/exim.git/commitdiff/4e6ae6235c68de243b1c2419027472d7659aa2b4
https://github.com/LetUsFsck/PoC-Exploit-Mirror/tree/master/CVE-2017-16944
https://lists.exim.org/lurker/message/20171125.034842.d1d75cac.en.html
https://www.debian.org/security/2017/dsa-4053
http://openwall.com/lists/oss-security/2017/11/25/1

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