CVE-2025-1020

criticalpriority · track · 39EPSS 0.005 · 45 %ileDEEUNLRUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.54% (45th) EPSS
CVSS 9.8 · critical
Is it mine?
40 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Memory safety bugs present in Firefox 134 and Thunderbird 134. 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 135 and Thunderbird 135.

01

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

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
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

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

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-119USCWE-787US
04

affected products (40)

Products and version ranges known to be affected.

showing 20 of 40
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • NCSC-2025-0040Kwetsbaarheden verholpen in Mozilla Firefox en ThunderbirdNL2025-02-07csaf · ncsc_nlNL

    Mozilla heeft kwetsbaarheden verholpen in Firefox en Thunderbird (Specifiek voor versies onder 135 en 128.7).

  • WID-SEC-W-2025-0262Mozilla Firefox und Thunderbird: Mehrere SchwachstellenDeutsch2025-02-04csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Mozilla Firefox, Mozilla Firefox ESR und Mozilla Thunderbird ausnutzen, um beliebigen Code auszuführen, vertrauliche Informationen preiszugeben, Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand zu erzeugen oder Spoofing-Angriffe durchzuführen.

06

also known as (6)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundncsc_nlNVDCVE.orgMITRE
published 2025-02-04modified 2026-10-05
09

references (11)

External citations — patches, advisories, analysis.

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