CVE-2026-84125
published 2026-09-01CVE-2026-84125: Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
PriorityP427medium5.4CVSS 3.1
AVNACLPRNUIRSUCLILAN
EPSS
0.16%
6.0th percentile
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 155 | Firefox 155 |
| mozilla | firefox | < 153.2.0 | 153.2.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 154.0.0 < 155.0.0 | 155.0.0 |
| mozilla | firefox_esr | < Firefox ESR 153.2 | Firefox ESR 153.2 |
| mozilla | thunderbird | < Thunderbird 153.2 | Thunderbird 153.2 |
| mozilla | thunderbird | < Thunderbird 155 | Thunderbird 155 |
| mozilla | thunderbird | < 153.2.0 | 153.2.0 |
| mozilla | thunderbird | >= 154.0 < 155.0 | 155.0 |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
vendor_redhat5.4MEDIUM
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Red Hat
firefox: Firefox: Arbitrary code execution via use-after-free in DOM: Core & HTML
vendor_redhat·2026-09-01·CVSS 5.4
CVE-2026-84125 [MEDIUM] CWE-825 firefox: Firefox: Arbitrary code execution via use-after-free in DOM: Core & HTML
firefox: Firefox: Arbitrary code execution via use-after-free in DOM: Core & HTML
A flaw was found in Firefox. A use-after-free vulnerability in the DOM: Core & HTML component could allow a remote attacker to execute arbitrary code.
Package: firefox (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 7) - Affected
Package: firefox (Red Hat Enterprise Linux 8) - Affected
Package: firefox (Red Hat Enterprise Linux 9) - Affected
Mozilla
Mozilla Foundation Security Advisory 2026-85: CVE-2026-84125
vendor_mozilla·CVSS 5.4
CVE-2026-84125 [MEDIUM] Mozilla Foundation Security Advisory 2026-85: CVE-2026-84125
Mozilla Foundation Security Advisory 2026-85
CVE: CVE-2026-84125
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-88: CVE-2026-84125
vendor_mozilla·CVSS 5.4
CVE-2026-84125 [MEDIUM] Mozilla Foundation Security Advisory 2026-88: CVE-2026-84125
Mozilla Foundation Security Advisory 2026-88
CVE: CVE-2026-84125
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-86: CVE-2026-84125
vendor_mozilla·CVSS 5.4
CVE-2026-84125 [MEDIUM] Mozilla Foundation Security Advisory 2026-86: CVE-2026-84125
Mozilla Foundation Security Advisory 2026-86
CVE: CVE-2026-84125
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 155
Mozilla
Mozilla Foundation Security Advisory 2026-82: CVE-2026-84125
vendor_mozilla·CVSS 5.4
CVE-2026-84125 [MEDIUM] Mozilla Foundation Security Advisory 2026-82: CVE-2026-84125
Mozilla Foundation Security Advisory 2026-82
CVE: CVE-2026-84125
Product: Firefox
Impact: high
Fixed in: Firefox 155
GHSA
Use-after-free in the DOM: Core & HTML component.
ghsa_unreviewed·2026-09-01
CVE-2026-84125 [MEDIUM] CWE-416 Use-after-free in the DOM: Core & HTML component.
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155 and Firefox ESR 153.2.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-84125 firefox: Firefox: Arbitrary code execution via use-after-free in DOM: Core & HTML
bugzilla·2026-09-01·CVSS 5.4
CVE-2026-84125 [MEDIUM] CVE-2026-84125 firefox: Firefox: Arbitrary code execution via use-after-free in DOM: Core & HTML
CVE-2026-84125 firefox: Firefox: Arbitrary code execution via use-after-free in DOM: Core & HTML
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155 and Firefox ESR 153.2.
Hackernews
⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More
blogs_hackernews·2026-09-07·CVSS 6.9
CVE-2026-86206 [MEDIUM] ⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More
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## ⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More
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2026-09-01
Published