CVE-2026-8879

Version 3.0.7 of the Securly Chrome Extension dynamically registers content13.min.js as a content script via chrome.scripting.registerContentScripts() at runtime. This script is NOT declared in manifest.json and bypasses Chrome Web Store static security review. It runs on all URLs and immediately hides all page content, creates a full-page overlay, pauses all videos, and only restores content when the service worker confirms the page passes filtering. If Securly's servers are unreachable, pages remain indefinitely hidden.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://kb.cert.org/vuls/id/595768	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:securly:securly:3.0.7:*:*:*:*:chrome:*:*

History

No history.

Information

Published : 2026-06-03 19:16

Updated : 2026-07-22 20:10

NVD link : CVE-2026-8879

Mitre link : CVE-2026-8879

CVE.ORG link : CVE-2026-8879

JSON object : View

Products Affected

securly

securly

CWE

CWE-829

Inclusion of Functionality from Untrusted Control Sphere

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