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.
https://git.exim.org/exim.git/commitdiff/4e6ae6235c68de243b1c2419027472d7659aa2b4
https://bugs.exim.org/show_bug.cgi?id=2199
https://lists.exim.org/lurker/message/20171125.034842.d1d75cac.en.html
https://github.com/LetUsFsck/PoC-Exploit-Mirror/tree/master/CVE-2017-16944
https://git.exim.org/exim.git/commit/4090d62a4b25782129cc1643596dc2f6e8f63bde
http://openwall.com/lists/oss-security/2017/11/25/3
http://openwall.com/lists/oss-security/2017/11/25/2
http://openwall.com/lists/oss-security/2017/11/25/1
http://www.securitytracker.com/id/1039872
Source: MITRE
Published: 2017-11-25
Updated: 2021-05-04
Type: CWE-416
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 10
Severity: HIGH
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 3.9
Severity: CRITICAL