CVE-2026-19986
Adblock for Youtube Extension Event Listener contentscript.js updateDynamicRules improper authorization
- State
- Published
- Severity
- 5.3 Medium
- Published
- Aug 17, 2026
- Updated
- Aug 19, 2026
- Reserved
- Aug 16, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.3 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:P | VulDB |
| 3.1 | 5.4 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L/E:P/RL:X/RC:R | VulDB |
| 3.0 | 5.4 Medium | CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L/E:P/RL:X/RC:R | VulDB |
| 2.0 | 6.4 Medium | AV:N/AC:L/Au:N/C:N/I:P/A:P/E:POC/RL:ND/RC:UR | VulDB |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
Adblock for Youtube Extensionn/a |
|
References
- VDB-391190 | Adblock for Youtube Extension Event Listener contentscript.js updateDynamicRules improper authorizationvdb-entrytechnical-description
- VDB-391190 | CTI Indicators (IOB, IOC, TTP, IOA)signaturepermissions-required
- CVE-2026-19986 | CVE Analysis and Reportthird-party-advisory
- Submit #873935 | AdBlock Ltd. Adblock for Youtube Chrome extension 7.2.1 Improper validation of event origin / authenticitythird-party-advisory
- 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%20eventexploitmedia-coverage
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.