HOMEVULNERABILITIESCVE-2026-8879
HIGH

CVE-2026-8879

Published: June 3, 2026· Updated: Jun 4, 2026

7.5
CVSS v3.1
EPSS:0.02%probability of exploitation in 30 daysPercentile:5.1th

Official 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.

NVD Source

Technical Analysis

CVE-2026-8879 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

securly1 product(s)
securly
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

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

All References (1)

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

Quick Facts

CVE IDCVE-2026-8879
CVSS Score7.5 / 10
SeverityHIGH
CISA KEVNo
EPSS (30d)0.02%
Affected1 vendor(s)
PublishedJun 3, 2026

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2026-8879 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
← All Vulnerabilities·Search for CVE-2026-8879·NVD