CVE-2026-8879
📛 CVE Title
CVE-2026-8879
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- certcc
- CVSS severity
- high
- CVSS score
- 7.5 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Effective score
- 7.5 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-829 Inclusion of Functionality from Untrusted Control Sphere - Reserved
- 2026-05-18
- Published
- 2026-06-03 18:11 UTC
- Last updated
- 2026-06-04 14:13 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8879.json
- Linked Threat
- CVE-2026-8879 — CVE-2026-8879
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-06-03 19:16:39 UTC
- NVD last modified
- 2026-06-17 11:04:33 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0037 (probability of exploitation in next 30 days)
- EPSS percentile
- 29.23% vs all CVEs — higher = more likely to be exploited, as of 2026-06-29
NVD-assigned CWE(s):
CWE-829
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-06-30 04:02 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-34165 - Assigner
- certcc
- Published
- Jun 3, 2026, 6:11:04 PM
- Updated
- Jun 4, 2026, 2:13:20 PM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EUVD-reported EPSS
- 0.3700
- Vendors
- Securly
- Products
-
Securly Chrome Extension (0 ≤3.0.7)
- Aliases
-
GHSA-jg8r-xqh5-556r
ENISA 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.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Securly | Securly Chrome Extension |
0 (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:securly:securly:3.0.7:*:*:*:*:chrome:*:*
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://kb.cert.org/vuls/id/595768 tenable:kb.cert.org
- https://nvd.nist.gov/vuln/detail/CVE-2026-8879 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-8879 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://kb.cert.org/vuls/id/595768 cret@cert.org Third Party Advisory
Remediations (16)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.qualys.com
May 2026's Patch Tuesday arrives with Microsoft addressing a fresh set of vulnerabilities across its ecosystem, reinforcing the ongoing need for timely patching in an increasingly threat-heavy…
2026-06-08 15:48 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-06-08 15:48 UTC -
web:inventivehq.com
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 ...
2026-06-08 15:48 UTC -
web:nvd.nist.gov
This is a potential security issue, you are being redirected to https://nvd.nist.gov
2026-06-08 15:48 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-06-08 15:48 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.
2026-06-08 15:48 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.
2026-06-08 15:48 UTC -
web:www.helpnetsecurity.com
The fix will be rolled into the June Patch Tuesday release. The June Patch Tuesday release will contain a fix for the failures and errors when installing KB5089549 for Windows 11.
2026-06-08 15:48 UTC -
web:www.rapid7.com
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday, including critical RCE in Netlogon and the Windows DNS client.
2026-06-08 15:48 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's June 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-06-08 15:48 UTC -
web:cybersecuritynews.com
Microsoft has officially acknowledged a critical zero-day vulnerability in Microsoft Defender, publicly dubbed "RoguePlanet," and confirmed it is actively developing a security patch to address the flaw.
2026-06-19 02:33 UTC -
web:nvd.nist.gov
This is a potential security issue, you are being redirected to https://nvd.nist.gov
2026-06-19 02:33 UTC -
web:support.microsoft.com
This update for Windows 11, version 25H2 and 24H2 (KB5084597) incudes security improvements. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of Windows software updates. To view the ...
2026-06-19 02:33 UTC -
web:www.crowdstrike.com
Microsoft's February 2026 Patch Tuesday addresses 59 CVEs , featuring six exploited vulnerabilities, three of which were publicly known, and five Critical vulnerabilities.
2026-06-19 02:33 UTC -
web:www.malwarebytes.com
Microsoft says it's working on a fix for an unpatched Defender vulnerability that can give attackers the highest level of access on Windows.
2026-06-19 02:33 UTC -
web:www.rapid7.com
Microsoft is publishing 200 vulnerabilities on June 2026 Patch Tuesday, including an HTTP/2 denial of service vulnerability and an elevation of privilege vulnerability in PowerToys.
2026-06-19 02:33 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-8879.json.
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"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
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"version": "3.1"
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"timestamp": "2026-06-04T14:12:27.850403Z",
"version": "2.0.3"
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"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
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"title": "CISA ADP Vulnrichment"
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"cna": {
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"vendor": "Securly",
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"shortName": "certcc"
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"references": [
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"source": {
"discovery": "UNKNOWN"
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"title": "CVE-2026-8879",
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"dateReserved": "2026-05-18T20:29:18.234Z",
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