CVE-2026-19986

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreHIGH confidence

Score 5.4 from GitHub Security Advisory (severity: LOW) published 2026-08-17. a secondary CVSS source baseline 5.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 5 sources updated this weekElevated
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

A weakness has been identified in Adblock for Youtube Extension up to 7.2.1 on Chrome. The impacted element is the function updateDynamicRules of the file contentscript.js of the component Event Listener. This manipulation of the argument yt-anti-adblock-detected causes improper authorization. It is possible to initiate the attack remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS v3
5.4
EG Score
5.4(high)
EG Risk
40(Track)
EG Risk 40/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity54% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
16%
KEV
Not listed

Published

August 17, 2026

Last Modified

August 20, 2026

Advisory Details (1)

Auto-updated Aug 17, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

chrome_extensions/AdBlock Ltd. Adblock for Youtube 7.2.1 allows persistent disabling of ad blocking through an unauthenticated DOM event at main · xryj920/chrome_extensions · GitHub

https://github.com/xryj920/chrome_extensions/blob/main/AdBlock%20Ltd.%20Adblock%20for%20Youtube%207.2.1%20allows%20persistent%20disabling%20of%20ad%20blocking%20through%20an%20unauthenticated%20DOM%20event

Vendor Advisories for CVE-2026-19986(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 20× in last 7d / 20× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-20 22:55 UTCEPSS rescore
  2. 2026-08-20 13:00 UTCEG score recompute
  3. 2026-08-20 13:00 UTCGHSA enrichment
  4. 2026-08-19 17:03 UTCEPSS rescore
  5. 2026-08-19 16:26 UTCEG score recompute
  6. 2026-08-19 16:26 UTCGHSA enrichment
  7. 2026-08-19 16:24 UTCNVD updateCVSS v4 → 2.1
  8. 2026-08-19 15:49 UTCEG score recompute
  9. 2026-08-19 15:49 UTCGHSA enrichment
  10. 2026-08-19 15:48 UTCMITRE cvelistV5CVSS v4 → 5.3
  11. 2026-08-19 03:13 UTCEG score recompute
  12. 2026-08-19 03:13 UTCGHSA enrichment
  13. 2026-08-18 13:48 UTCEPSS rescore
  14. 2026-08-18 04:21 UTCEG score recompute
  15. 2026-08-18 04:21 UTCGHSA enrichment
  16. 2026-08-17 13:47 UTCEPSS rescore
  17. 2026-08-17 05:29 UTCEG score recompute
  18. 2026-08-17 05:28 UTCNVD updateCVSS v4 → 2.1
  19. 2026-08-17 05:06 UTCEG score recompute
  20. 2026-08-17 05:05 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-19986?
CVE-2026-19986 is a medium vulnerability published on August 17, 2026. A weakness has been identified in Adblock for Youtube Extension up to 7.2.1 on Chrome. The impacted element is the function updateDynamicRules of the file contentscript.js of the component Event Listener. This manipulation of the argument yt-anti-adblock-detected causes improper authorization. It…
When was CVE-2026-19986 disclosed?
CVE-2026-19986 was first published in the National Vulnerability Database on August 17, 2026, with the most recent update on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-19986 actively exploited?
CVE-2026-19986 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 84.3% of all scored CVEs.
What is the CVSS score of CVE-2026-19986?
CVE-2026-19986 has a CVSS v3 base score of 5.4 (NVD).
How do I remediate CVE-2026-19986?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-19986, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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