CVE-2026-5731

criticalpriority · track · 0EPSS 0.006 · 49 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.61% (49th) EPSS
CVSS 9.8 · critical
Is it mine?
35 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-22

Memory safety bugs present in Firefox ESR 115.34.0, Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 149.0.2, Firefox ESR 115.34.1, Firefox ESR 140.9.1, Thunderbird 149.0.2, and Thunderbird 140.9.1.

01

remediations

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

A vendor fix is available.

  • FixedMozillaThunderbird-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-branding-upstream-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-branding-upstream-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-branding-upstream-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-branding-upstream-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-common-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-common-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-common-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-common-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-other-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-other-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-other-0:140.9.1-1.1.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".

  • Fixedfirefox-esr-translations-other-0:140.9.1-1.1.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".

02

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

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
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondaryexploitability 2.8 · impact 5.9
v3.17.5highCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · SUSE Product Security
03

ssvc

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

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-119USCWE-119USCWE-787US
05

affected products (35)

Products and version ranges known to be affected.

showing 20 of 35
06

advisories (5)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-0997Mozilla Firefox und Thunderbird: Mehrere SchwachstellenDeutsch2026-04-07csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Mozilla Firefox und Mozilla Thunderbird ausnutzen, um einen Denial-of-Service-Zustand herbeizuführen, beliebigen Code auszuführen oder andere, nicht näher spezifizierte Angriffe durchzuführen.

  • WID-SEC-W-2026-1730Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2026-05-28csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

  • WID-SEC-W-2026-2455Oracle Solaris Drittanbieterkomponenten: Mehrere SchwachstellenDeutsch2026-07-21csaf · cert_bundDE

    Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in verschiedenen Komponenten von Drittanbietern in Oracle Solaris ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

  • openSUSE-SU-2026:10501-1MozillaThunderbird-140.9.1-1.1 on GA media2026-04-08csaf · suse_csafDE

    MozillaThunderbird-140.9.1-1.1 on GA media

  • openSUSE-SU-2026:10503-1firefox-esr-140.9.1-1.1 on GA media2026-04-08csaf · suse_csafDE

    firefox-esr-140.9.1-1.1 on GA media

07

also known as (9)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundsuse_csafNVDCVE.orgMITRE
published 2026-04-07modified 2026-09-22
09

references (45)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan