CVE-2026-40684

highpriority · track · 30EPSS 0.004 · 30 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.36% (30th) EPSS

CVSS 7.5 · high

Is it mine?

29 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-25

In Exim before 4.99.2, on systems using musl libc (not glibc), an attacker can crash the connection instance when malformed DNS data is present in PTR records. This is caused by a dn_expand oddity in octal printing.

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · cve@mitre.org USexploitability 2.2 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-684USCWE-684US

affected products (29)

Products and version ranges known to be affected.

Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Open Source Exim <4.99.2all versionscert_bundDE
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
cPanel cPanel/WHM 126.0.63all versionscert_bundDEcpe:/a:cpanel:cpanel_whm:126.0.63
cPanel cPanel/WHM <110.0.112all versionscert_bundDE
cPanel cPanel/WHM <118.0.64all versionscert_bundDE
cPanel cPanel/WHM <126.0.56all versionscert_bundDE
cPanel cPanel/WHM <134.0.23all versionscert_bundDE
cPanel cPanel/WHM <134.0.30all versionscert_bundDE
cPanel cPanel/WHM <136.0.14all versionscert_bundDE
cPanel cPanel/WHM <136.0.7all versionscert_bundDE
cPanel cPanel/WHM <137.9999.96all versionscert_bundDE
Open Source Exim< 4.99.2cert_bundDE
cPanel cPanel/WHM< 110.0.112cert_bundDE
cPanel cPanel/WHM< 118.0.64cert_bundDE
cPanel cPanel/WHM< 126.0.56cert_bundDE
cPanel cPanel/WHM< 134.0.23cert_bundDE
cPanel cPanel/WHM< 134.0.30cert_bundDE
cPanel cPanel/WHM< 136.0.14cert_bundDE

showing 20 of 29

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-1334Exim und cPanel/WHM: Mehrere SchwachstellenDeutsch2026-05-03csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Exim und cPanel cPanel/WHM ausnutzen, um einen Denial of Service Angriff durchzuführen, Daten zu manipulieren oder vertrauliche Informationen offenzulegen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund NVD CVE.org MITRE

published 2026-04-30modified 2026-09-04

references (11)

External citations — patches, advisories, analysis.

scry

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