Exim SMTP Challenge Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability.
The specific flaw exists within the handling of NTLM challenge requests. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the service account. . Was ZDI-CAN-17515.
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)
- CVSS 3.0 Base Score: 8.1
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | alpine-linux-upgrade-exim | Aug 22, 2024 | May 3, 2024 | |
| Amazon_linux | — | amazon-linux-upgrade-exim | May 13, 2025 | Oct 24, 2023 |
| Debian | debian-upgrade-exim4 | Oct 4, 2023 | Oct 4, 2023 | |
| Exim | exim-upgrade-latest | Apr 7, 2026 | May 3, 2024 | |
| Gentoo Linux | gentoo-linux-upgrade-mail-mta-exim | Feb 19, 2024 | Feb 18, 2024 | |
| Suse | — | suse-upgrade-eximsuse-upgrade-eximonsuse-upgrade-eximstats-html | Oct 6, 2023 | Oct 5, 2023 |
| Ubuntu | ubuntu-pro-upgrade-exim4ubuntu-pro-upgrade-exim4-baseubuntu-pro-upgrade-exim4-daemon-heavyubuntu-pro-upgrade-exim4-daemon-lightubuntu-pro-upgrade-eximon4ubuntu-upgrade-exim4ubuntu-upgrade-exim4-baseubuntu-upgrade-exim4-daemon-heavyubuntu-upgrade-exim4-daemon-lightubuntu-upgrade-eximon4 | Oct 6, 2023 | Oct 4, 2023 |
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