Exim Buffer Overflow Vulnerability

Exim contains a buffer overflow vulnerability in the base64d function part of the SMTP listener that may allow for remote code execution.

Published 2 Oct 2026Updated 2 Oct 2026440 sources

CVSS 9.8 ✓ VERIFIED REFERENCE△ CISA KEV

Overview Sources History

What happened

Exim contains a buffer overflow vulnerability in the base64d function part of the SMTP listener that may allow for remote code execution.

Affected versions

Exim: See original advisory Fixed: See vendor advisory.

Why it matters

This source correlation may provide earlier visibility while structured CVE metadata is still being updated.

Detection & mitigation

Review the original advisory and validate affected versions.
Apply vendor-provided updates or mitigations when available.

Public PoC references

RepositoryAuthorFirst seenReference

Exploit-DB 45671exim 4.90 - Remote Code Executionhackk.gr2018-10-24Verified Exploit-DB 44571Exim < 4.90.1 - 'base64d' Remote Code Executionstraight_blast2018-05-02Verified SploitusExim 4.89 vulnerability CVE-2018-6789 with plaintext and TLS authentication.KitPloit2026-09-23T00:59:21Candidate kitploit.comExim 4.89 vulnerability CVE-2018-6789 with plaintext and TLS authentication.zh2026-09-23T00:59:21Candidate

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