Is CVE-2018-6789 actively exploited?

CVE-2018-6789 has no public evidence of in-the-wild exploitation as of 2025-11-07.

What is the CVSS score for CVE-2018-6789?

CVE-2018-6789 has a CVSS score of 9.8 (CRITICAL severity). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

How do I patch CVE-2018-6789?

Patch guidance is available from exim security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2018-6789.

Fix CVE-2018-6789 - CRITICAL exim exim

Q: Which products are affected by CVE-2018-6789?

7 products: exim exim, debian debian linux, debian debian linux, debian debian linux, canonical ubuntu linux, and 2 more.

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.

CVSS Metrics

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector: network
Complexity: low
Privileges: none
User Action: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high
Weaknesses: CWE-120 CWE-120

Metadata

Primary Vendor: EXIM
Published: 2/8/2018
Last Modified: 11/7/2025
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

exim : eximdebian : debian_linuxdebian : debian_linuxdebian : debian_linuxcanonical : ubuntu_linuxcanonical : ubuntu_linuxcanonical : ubuntu_linux

Remediation Guidance

Executive Summary

View on NIST NVD