CVE-2025-6424
published 2025-06-24CVE-2025-6424: A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability was fixed in Firefox 140, Firefox ESR 115.25, Firefox ESR…
PriorityP354critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
3.12%
86.4th percentile
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability was fixed in Firefox 140, Firefox ESR 115.25, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| debian | firefox-esr | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| debian | thunderbird | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| mozilla | firefox | < 115.25.0 | 115.25.0 |
| mozilla | firefox | < 140.0 | 140.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 116.0 < 128.12.0 | 128.12.0 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1~deb11u1 | 1:128.12.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1~deb12u1 | 1:128.12.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1 | 1:128.12.0esr-1 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1 | 1:128.12.0esr-1 |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2025-07-22
CVE-2025-4083 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context, an
attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, bypass security restrictions, cross-site
tracing, or execute arbitrary code.
Instructions: This update uses a new upstream release, which includes additional bug
fixes. After a standard system update you need to restart thunderbird to
make all the necessary changes.
Red Hat
firefox: thunderbird: Use-after-free in FontFaceSet
vendor_redhat·2025-06-24·CVSS 9.8
CVE-2025-6424 [CRITICAL] CWE-416 firefox: thunderbird: Use-after-free in FontFaceSet
firefox: thunderbird: Use-after-free in FontFaceSet
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability affects Firefox < 140, Firefox ESR < 115.25, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
A use-after-free in FontFaceSet resulted in a potentially exploitable crash.
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of suppor
Debian
CVE-2025-6424: firefox - A use-after-free in FontFaceSet resulted in a potentially exploitable crash. Thi...
vendor_debian·2025·CVSS 9.8
CVE-2025-6424 [CRITICAL] CVE-2025-6424: firefox - A use-after-free in FontFaceSet resulted in a potentially exploitable crash. Thi...
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability affects Firefox < 140, Firefox ESR < 115.25, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
Scope: local
sid: resolved (fixed in 140.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-51: CVE-2025-6424
vendor_mozilla·CVSS 9.8
CVE-2025-6424 [CRITICAL] Mozilla Foundation Security Advisory 2025-51: CVE-2025-6424
Mozilla Foundation Security Advisory 2025-51
CVE: CVE-2025-6424
Product: Firefox
Impact: high
Fixed in: Firefox 140
Mozilla
Mozilla Foundation Security Advisory 2025-52: CVE-2025-6424
vendor_mozilla·CVSS 9.8
CVE-2025-6424 [CRITICAL] Mozilla Foundation Security Advisory 2025-52: CVE-2025-6424
Mozilla Foundation Security Advisory 2025-52
CVE: CVE-2025-6424
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 115.25
Mozilla
Mozilla Foundation Security Advisory 2025-53: CVE-2025-6424
vendor_mozilla·CVSS 9.8
CVE-2025-6424 [CRITICAL] Mozilla Foundation Security Advisory 2025-53: CVE-2025-6424
Mozilla Foundation Security Advisory 2025-53
CVE: CVE-2025-6424
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 128.12
Mozilla
Mozilla Foundation Security Advisory 2025-55: CVE-2025-6424
vendor_mozilla·CVSS 9.8
CVE-2025-6424 [CRITICAL] Mozilla Foundation Security Advisory 2025-55: CVE-2025-6424
Mozilla Foundation Security Advisory 2025-55
CVE: CVE-2025-6424
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 128.12
Mozilla
Mozilla Foundation Security Advisory 2025-54: CVE-2025-6424
vendor_mozilla·CVSS 9.8
CVE-2025-6424 [CRITICAL] Mozilla Foundation Security Advisory 2025-54: CVE-2025-6424
Mozilla Foundation Security Advisory 2025-54
CVE: CVE-2025-6424
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140
GHSA
GHSA-87c4-94w2-rw7j: A use-after-free in FontFaceSet resulted in a potentially exploitable crash
ghsa_unreviewed·2025-06-26
CVE-2025-6424 [CRITICAL] CWE-416 GHSA-87c4-94w2-rw7j: A use-after-free in FontFaceSet resulted in a potentially exploitable crash
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability affects Firefox < 140, Firefox ESR < 115.25, and Firefox ESR < 128.12.
OSV
CVE-2025-6424: A use-after-free in FontFaceSet resulted in a potentially exploitable crash
osv·2025-06-24·CVSS 9.8
CVE-2025-6424 [CRITICAL] CVE-2025-6424: A use-after-free in FontFaceSet resulted in a potentially exploitable crash
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability affects Firefox < 140, Firefox ESR < 115.25, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
No detection rules found.
No public exploits indexed.
Checkpoint
30th June – Threat Intelligence Report
blogs_checkpoint·2025-06-30
CVE-2025-20281 30th June – Threat Intelligence Report
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## 30th June – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 29th June, please download our Threat Intelligence Bulletin .
TOP ATTACKS AND BREACHES
Grocery giant Ahold Delhaize has disclosed a data breach that resulted in the theft of personal, financial, employment, and health information belonging to over 2.2 million individuals from its American business systems. The leaked data includes names, contact details, IDs, bank account numbers, and medical information . While
Bugzilla
CVE-2025-6424 firefox: thunderbird: Use-after-free in FontFaceSet
bugzilla·2025-06-24·CVSS 9.8
CVE-2025-6424 [CRITICAL] CVE-2025-6424 firefox: thunderbird: Use-after-free in FontFaceSet
CVE-2025-6424 firefox: thunderbird: Use-after-free in FontFaceSet
A use-after-free in FontFaceSet resulted in a potentially exploitable crash. This vulnerability affects Firefox < 140, Firefox ESR < 115.25, and Firefox ESR < 128.12.
Discussion:
This issue has been addressed in the following products:
Red Hat Enterprise Linux 8
Via RHSA-2025:10074 https://access.redhat.com/errata/RHSA-2025:10074
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 10
Via RHSA-2025:10073 https://access.redhat.com/errata/RHSA-2025:10073
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 9
Via RHSA-2025:10072 https://access.redhat.com/errata/RHSA-2025:10072
---
This issue has been addressed in the following products:
Red Hat En
https://bugzilla.mozilla.org/show_bug.cgi?id=1966423https://www.mozilla.org/security/advisories/mfsa2025-51/https://www.mozilla.org/security/advisories/mfsa2025-52/https://www.mozilla.org/security/advisories/mfsa2025-53/https://www.mozilla.org/security/advisories/mfsa2025-54/https://www.mozilla.org/security/advisories/mfsa2025-55/https://lists.debian.org/debian-lts-announce/2025/06/msg00029.htmlhttps://lists.debian.org/debian-lts-announce/2025/07/msg00002.html
2025-06-24
Published