CVE-2026-84137
published 2026-09-01CVE-2026-84137: Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
PriorityP418medium4.3CVSS 3.1
AVNACLPRNUIRSUCNILAN
EPSS
0.13%
2.8th percentile
Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 155 | Firefox 155 |
| mozilla | firefox | < 153.2.0 | 153.2.0 |
| 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 155 | Thunderbird 155 |
| mozilla | thunderbird | < Thunderbird 153.2 | Thunderbird 153.2 |
| mozilla | thunderbird | < 153.2.0 | 153.2.0 |
| mozilla | thunderbird | >= 154.0 < 155.0 | 155.0 |
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Mozilla
Mozilla Foundation Security Advisory 2026-86: CVE-2026-84137
vendor_mozilla
CVE-2026-84137 Mozilla Foundation Security Advisory 2026-86: CVE-2026-84137
Mozilla Foundation Security Advisory 2026-86
CVE: CVE-2026-84137
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 155
Mozilla
Mozilla Foundation Security Advisory 2026-82: CVE-2026-84137
vendor_mozilla
CVE-2026-84137 Mozilla Foundation Security Advisory 2026-82: CVE-2026-84137
Mozilla Foundation Security Advisory 2026-82
CVE: CVE-2026-84137
Product: Firefox
Impact: high
Fixed in: Firefox 155
Mozilla
Mozilla Foundation Security Advisory 2026-85: CVE-2026-84137
vendor_mozilla
CVE-2026-84137 Mozilla Foundation Security Advisory 2026-85: CVE-2026-84137
Mozilla Foundation Security Advisory 2026-85
CVE: CVE-2026-84137
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-88: CVE-2026-84137
vendor_mozilla
CVE-2026-84137 Mozilla Foundation Security Advisory 2026-88: CVE-2026-84137
Mozilla Foundation Security Advisory 2026-88
CVE: CVE-2026-84137
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153.2
VulDB
Mozilla Firefox up to 153.1/154 DOM/HTML HTML injection (Nessus ID 342317)
vuldb·2026-09-03
CVE-2026-84137 [LOW] Mozilla Firefox up to 153.1/154 DOM/HTML HTML injection (Nessus ID 342317)
A vulnerability marked as problematic has been reported in Mozilla Firefox up to 153.1/154. This affects an unknown function of the component DOM/HTML. The manipulation leads to HTML injection.
This vulnerability is referenced as CVE-2026-84137. Remote exploitation of the attack is possible. No exploit is available.
It is suggested to upgrade the affected component.
GHSA
Spoofing issue in the DOM: Core & HTML component.
ghsa_unreviewed·2026-09-01
CVE-2026-84137 Spoofing issue in the DOM: Core & HTML component.
Spoofing issue 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.
No writeups or analysis indexed.
2026-09-01
Published