CVE-2018-6789

Known Exploited Public Exploit

Description

An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1. By sending a handcrafted message, a buffer overflow may happen. This can be used to execute code remotely.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 72.08% Top 5%
KEV Since 
Vendor Advisory ubuntu.com Vendor Advisory debian.org Vendor Advisory exim.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://exim.org/static/doc/security/CVE-2018-6789.txt vendor advisory
http://www.openwall.com/lists/oss-security/2018/02/07/2 third party advisory mailing list
https://usn.ubuntu.com/3565-1/ third party advisory vendor advisory
http://openwall.com/lists/oss-security/2018/02/10/2 third party advisory mailing list
http://www.securitytracker.com/id/1040461 broken link third party advisory vdb entry
https://www.debian.org/security/2018/dsa-4110 vendor advisory mailing list third party advisory
https://www.exploit-db.com/exploits/44571/ third party advisory vdb entry exploit
https://lists.debian.org/debian-lts-announce/2018/02/msg00009.html third party advisory mailing list
https://git.exim.org/exim.git/commit/cf3cd306062a08969c41a1cdd32c6855f1abecf1 patch
https://devco.re/blog/2018/03/06/exim-off-by-one-RCE-exploiting-CVE-2018-6789-en/ third party advisory exploit
http://www.securityfocus.com/bid/103049 broken link third party advisory vdb entry
https://www.exploit-db.com/exploits/45671/ third party advisory vdb entry exploit
http://packetstormsecurity.com/files/162959/Exim-base64d-Buffer-Overflow.html third party advisory vdb entry exploit

Frequently Asked Questions

What is the severity of CVE-2018-6789?
CVE-2018-6789 has been scored as a critical severity vulnerability.
How to fix CVE-2018-6789?
To fix CVE-2018-6789, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-6789 being actively exploited in the wild?
It is confirmed that CVE-2018-6789 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~72% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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