critical
CVE-2018-6789
exim: buffer overflow in b64decode() function, possibly leading to remote code execution
In the Trivy database since at least 24 Oct 2026, 07:11 UTCWhen it arrived before that build is not recorded.
Severity by source
NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Red Hat8.1CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Trivy's own label is CRITICAL. Rated critical by NVD, Red Hat, Amazon. Rated lower by Ubuntu (medium).
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.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| amazon linux 1 | exim, exim-debuginfo, exim-greylist and 3 more | 4.90.1-2.14.amzn1 |
| alpine 3.10 | exim | 4.90.1-r0 |
| alpine 3.11 | exim | 4.90.1-r0 |
| alpine 3.12 | exim | 4.90.1-r0 |
| alpine 3.13 | exim | 4.90.1-r0 |
| alpine 3.14 | exim | 4.90.1-r0 |
| alpine 3.15 | exim | 4.90.1-r0 |
| alpine 3.16 | exim | 4.90.1-r0 |
| alpine 3.17 | exim | 4.90.1-r0 |
| alpine 3.18 | exim | 4.90.1-r0 |
| alpine 3.19 | exim | 4.90.1-r0 |
| alpine 3.20 | exim | 4.90.1-r0 |
Show all 38 entries from 33 sources
| Source | Package | Fixed in |
|---|---|---|
| amazon linux 1 | exim | 4.90.1-2.14.amzn1 |
| amazon linux 1 | exim-debuginfo | 4.90.1-2.14.amzn1 |
| amazon linux 1 | exim-greylist | 4.90.1-2.14.amzn1 |
| amazon linux 1 | exim-mon | 4.90.1-2.14.amzn1 |
| amazon linux 1 | exim-mysql | 4.90.1-2.14.amzn1 |
| amazon linux 1 | exim-pgsql | 4.90.1-2.14.amzn1 |
| alpine 3.10 | exim | 4.90.1-r0 |
| alpine 3.11 | exim | 4.90.1-r0 |
| alpine 3.12 | exim | 4.90.1-r0 |
| alpine 3.13 | exim | 4.90.1-r0 |
| alpine 3.14 | exim | 4.90.1-r0 |
| alpine 3.15 | exim | 4.90.1-r0 |
| alpine 3.16 | exim | 4.90.1-r0 |
| alpine 3.17 | exim | 4.90.1-r0 |
| alpine 3.18 | exim | 4.90.1-r0 |
| alpine 3.19 | exim | 4.90.1-r0 |
| alpine 3.20 | exim | 4.90.1-r0 |
| alpine 3.21 | exim | 4.90.1-r0 |
| alpine 3.22 | exim | 4.90.1-r0 |
| alpine 3.23 | exim | 4.90.1-r0 |
| alpine 3.24 | exim | 4.90.1-r0 |
| alpine 3.7 | exim | 4.90.1-r0 |
| alpine 3.8 | exim | 4.90.1-r0 |
| alpine 3.9 | exim | 4.90.1-r0 |
| alpine edge | exim | 4.90.1-r0 |
| debian 11 | exim4 | 4.90.1-1 |
| debian 12 | exim4 | 4.90.1-1 |
| debian 13 | exim4 | 4.90.1-1 |
| debian 14 | exim4 | 4.90.1-1 |
| debian 7 | exim4 | 4.80-7+deb7u6 |
| debian 8 | exim4 | 4.84.2-2+deb8u5 |
| debian 9 | exim4 | 4.89-2+deb9u3 |
| echo | exim4 | 4.90.1-1 |
| ubuntu 14.04 | exim4 | 4.82-3ubuntu2.4 |
| ubuntu 14.04-ESM | exim4 | 4.82-3ubuntu2.4 |
| ubuntu 16.04 | exim4 | 4.86.2-2ubuntu2.3 |
| ubuntu 16.04-ESM | exim4 | 4.86.2-2ubuntu2.3 |
| ubuntu 17.10 | exim4 | 4.89-5ubuntu1.3 |
References
- http://openwall.com/lists/oss-security/2018/02/10/2
- http://packetstormsecurity.com/files/162959/Exim-base64d-Buffer-Overflow.html
- http://www.openwall.com/lists/oss-security/2018/02/07/2
- http://www.securityfocus.com/bid/103049
- http://www.securitytracker.com/id/1040461
- https://access.redhat.com/security/cve/CVE-2018-6789
- https://devco.re/blog/2018/03/06/exim-off-by-one-RCE-exploiting-CVE-2018-6789-en/
- https://exim.org/static/doc/security/CVE-2018-6789.txt
All 19 references
- https://git.exim.org/exim.git/commit/cf3cd306062a08969c41a1cdd32c6855f1abecf1
- https://lists.debian.org/debian-lts-announce/2018/02/msg00009.html
- https://nvd.nist.gov/vuln/detail/CVE-2018-6789
- https://ubuntu.com/security/notices/USN-3565-1
- https://usn.ubuntu.com/3565-1/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-6789
- https://www.cve.org/CVERecord?id=CVE-2018-6789
- https://www.debian.org/security/2018/dsa-4110
- https://www.exploit-db.com/exploits/44571/
- https://www.exploit-db.com/exploits/45671/