CVE-2018-6789

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.821 · 100 %ileexploit · PoCEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 7 exploits · PoC

Likely / severe?

82.1% (100th) EPSS

CVSS 7.5 · high

Is it mine?

14 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2021-11-03remediate by 2022-05-03

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-24

Exim Buffer Overflow Vulnerability

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

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondaryexploitability 3.9 · impact 5.9

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USprimaryCWE-119US

ATT&CK techniques

ATT&CK techniques this enables or maps to.

exploits (7)

Public proof-of-concept and weaponised exploit code.

EDB-44571Exim < 4.90.1 - 'base64d' Remote Code ExecutionPoC · exploit_db
EDB-45671exim 4.90 - Remote Code ExecutionPoC · exploit_db
beraphin/CVE-2018-6789beraphin/CVE-2018-6789PoC · poc_in_github
c0llision/exim-vuln-pocCVE-2018-6789PoC · poc_in_github
martinclauss/exim-rce-cve-2018-6789This repository provides a learning environment to understand how an Exim RCE exploit for CVE-2018-6789 works.PoC · poc_in_github
synacktiv/Exim-CVE-2018-6789PoC materials to exploit CVE-2018-6789PoC · poc_in_github

affected products (14)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
GNU General Public License exim≤ 4.90.1fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 8fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 7fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
canonical ubuntu linux= 14.04nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
canonical ubuntu linux= 16.04nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
canonical ubuntu linux= 17.10nvdUScpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:*:*:*:*
debian debian linux= 7.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 8.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
exim exim< 4.90.1nvdUScpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2018-02-08modified 2026-06-17

related (5,661)

Related entries.

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+5656 more

references (43)

External citations — patches, advisories, analysis.

scry

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