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CVE-2026-100822: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-100822cvecve-2026-100822
Published: 09/29/2026 (09/29/2026, 12:36:30 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Spoofing issue in the Networking: HTTP component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.

Affected software

Mozilla

Firefox

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
<153.4

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/29/2026, 13:03:16 UTC

Technical Analysis

CVE-2026-100822 is a spoofing vulnerability affecting the Networking: HTTP component in Mozilla Firefox. The flaw could allow an attacker to spoof network communications. Mozilla fixed this vulnerability in Firefox ESR 153.4 and Firefox 157. The vendor advisory categorizes the impact as high and recommends updating to the fixed versions. There is no indication of active exploitation in the wild.

Potential Impact

The vulnerability allows spoofing in the HTTP networking component, which could potentially lead to misleading or deceptive network communications. Mozilla rates the impact as high. There are no reports of known exploits in the wild at this time.

Mitigation Recommendations

Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4 and Firefox 157. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-09-26T19:18:38.463Z
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"}]

Threat ID: 6abbb3f7f7a7c541066409c2

Added to database: 09/29/2026, 12:49:59 UTC

Last enriched: 09/29/2026, 13:03:16 UTC

Last updated: 09/29/2026, 18:20:13 UTC

Views: 8

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