Vulnerability Report

CVE-2026-8879

Title: Undocumented content script bypass

Other

Proof Of Concept

No public PoC currently indexed for CVE-2026-8879.

CWE Category NVD-CWE-noinfo

Published Date Jun 03, 2026

Modified Date Jul 22, 2026

Exploit Status Not Found

Score 7.5 CVSS v

Exploit Probability (EPSS)

0.37%

Vulnerability Summary

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.

Impacted Vendors

securly 1

Reference Links

https://kb.cert.org/vuls/id/595768

CVSS v3.1

Source Entity 134c704f-9b21-4f2e-91b3-4a467353bcc0

Severity HIGH

7.5

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-8879 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

July 22, 2026 MODIFIED

Vulnerability data updated via NVD.

June 04, 2026 MODIFIED

Vulnerability data updated via NVD.

June 04, 2026 MODIFIED

Vulnerability data updated via NVD.

June 03, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


                                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Stack

No specific products linked.