CVE-2026-8879

HIGH

Securly Chrome Extension < 3.0.7 - Denial of Service via Dynamic Content Script Injection

Title source: llm
STIX 2.1

Description

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.

References (1)

Core 1

Scores

CVSS v3 7.5
EPSS 0.0029
EPSS Percentile 20.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-829
Status published
Products (2)
securly/securly 3.0.7
Securly/Securly Chrome Extension < 3.0.7
Published Jun 03, 2026
Tracked Since Jun 04, 2026