CVE-2026-4371

highpriority · track · 0EPSS 0.004 · 30 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.37% (30th) EPSS

CVSS 7.4 · high

Is it mine?

22 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer. If a mail server or connection to a mail server were compromised, an attacker could cause the parser to malfunction, potentially crashing Thunderbird or leaking sensitive data. This vulnerability was fixed in Thunderbird 149 and Thunderbird 140.9.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedthunderbird-0:140.9.0-1.el9_7.x86_64 as component of SUSE Liberty Linux 9suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedthunderbird-0:140.9.0-1.el10_1.x86_64 as component of SUSE Liberty Linux 10suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Fixedthunderbird-0:140.9.0-1.el8_10.x86_64 as component of SUSE Liberty Linux 8suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.aarch64 as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.aarch64 as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.ppc64le as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.ppc64le as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.s390x as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.s390x as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.x86_64 as component of SUSE Linux Enterprise Workstation Extension 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-150200.8.263.1.x86_64 as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.aarch64 as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.aarch64 as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.ppc64le as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.ppc64le as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.s390x as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.s390x as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.x86_64 as component of SUSE Linux Enterprise Workstation Extension 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-150200.8.263.1.x86_64 as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.aarch64 as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.aarch64 as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.ppc64le as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.ppc64le as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.s390x as component of SUSE Linux Enterprise Module for Package Hub 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.s390x as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.x86_64 as component of SUSE Linux Enterprise Workstation Extension 15 SP7suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-150200.8.263.1.x86_64 as component of openSUSE Leap 15.6suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-1.1.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-1.1.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-1.1.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-0:140.9.0-1.1.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-openpgp-librnp-0:140.9.0-1.1.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-openpgp-librnp-0:140.9.0-1.1.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-openpgp-librnp-0:140.9.0-1.1.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-openpgp-librnp-0:140.9.0-1.1.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-1.1.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-1.1.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-1.1.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-common-0:140.9.0-1.1.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-1.1.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-1.1.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-1.1.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
FixedMozillaThunderbird-translations-other-0:140.9.0-1.1.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

cvss

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

8.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.5–8.2

v3.17.4highAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · ENISA EU

v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondaryexploitability 2.2 · impact 5.2

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Hsecondaryexploitability 3.9 · impact 4.2

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · SUSE Product Security

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-126USCWE-126USCWE-130US

affected products (22)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Mozilla Firefox< 149cert_bundDE
Mozilla Firefox ESR< 115.34cert_bundDE
Mozilla Firefox ESR< 140.9cert_bundDE
Mozilla Thunderbird≤ ESR <140.9cert_bundDE
Mozilla Thunderbird< 149cert_bundDE
Mozilla Corp. Thunderbird≤ 140.9fstec_bduRU
Mozilla Corp. Thunderbird141.0 → 149.0fstec_bduRU
АО «НППКТ» ОСОН ОСнова 3 Оnyx≤ 3.2fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.15fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.8fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.8fstec_bduRU

showing 20 of 22

advisories (6)

Vendor and ecosystem advisories describing this.

RHSA-2026:6188security update for thunderbird2026-03-30csaf · suse_csafDE
security update for thunderbird
RHSA-2026:6342security update for thunderbird2026-04-01csaf · suse_csafDE
security update for thunderbird
RHSA-2026:6917security update for thunderbird2026-04-07csaf · suse_csafDE
security update for thunderbird
SUSE-SU-2026:1163-1Security update for MozillaThunderbird2026-04-01csaf · suse_csafDE
Security update for MozillaThunderbird
WID-SEC-W-2026-0850Mozilla Firefox und Mozilla Thunderbird: Mehrere SchwachstellenDeutsch2026-03-24csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Mozilla Firefox und Mozilla Thunderbird ausnutzen, um beliebigen Code auszuführen, um einen Denial of Service herbeizuführen, um Informationen offenzulegen, um Sicherheitsmechanismen zu umgehen, um den Benutzer zu täuschen und um nicht näher spezifizierte Auswirkungen zu erzielen.
openSUSE-SU-2026:10447-1MozillaThunderbird-140.9.0-1.1 on GA media2026-03-28csaf · suse_csafDE
MozillaThunderbird-140.9.0-1.1 on GA media

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 suse_csaf NVD CVE.org MITRE

published 2026-03-24modified 2026-09-23

references (25)

External citations — patches, advisories, analysis.

scry

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