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CVE-2026-109773: Vulnerability in Mozilla Firefox

0
Medium
VulnerabilityCVE-2026-109773cvecve-2026-109773
Published: 10/13/2026 (10/13/2026, 12:29:34 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Denial-of-service in the Sync component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

CVSS v3.1

Score 6.5medium

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected software

Mozilla

Firefox

Mozilla

Thunderbird

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
<158

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 10/13/2026, 13:19:22 UTC

Technical Analysis

CVE-2026-109773 is a denial-of-service vulnerability affecting the Sync component of Mozilla Firefox. The flaw could allow an attacker to disrupt normal operation by causing the browser to crash or hang. Mozilla fixed this vulnerability in Firefox 158.

Potential Impact

Successful exploitation of this vulnerability could result in denial of service, causing Firefox to become unresponsive or crash. There is no indication of code execution or data compromise from the provided information.

Mitigation Recommendations

Users should update to Firefox version 158 or later to remediate this vulnerability. Since an official fix is available, applying this update fully mitigates the issue.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-10-13T00:48:58.340Z
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"}]

Threat ID: 6ace2c512cdf04f65661d573

Added to database: 10/13/2026, 13:04:17 UTC

Last enriched: 10/13/2026, 13:19:22 UTC

Last updated: 10/13/2026, 18:57:33 UTC

Views: 7

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