CVE-2018-6789

exim: buffer overflow in b64decode() function, possibly leading to remote code execution

Published Feb 8, 2018 CVSS 3.1 · 9.8 Critical EPSS 82.1% KEV · Listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-1274-1 exim4 security update
Debian DSA Debian DSA DSA-4110-1 exim4 security update
Ubuntu USN Ubuntu USN USN-3565-1 Exim vulnerability
Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Oct 21, 2025, 11:45 PM
Reserved
Feb 6, 2018, 12:00 AM
Status
Analyzed
Published
Feb 8, 2018, 11:29 PM
Modified
Jun 17, 2026, 2:02 AM
Severity
Critical
Public date
Feb 7, 2018, 12:00 AM