CVE-2026-44658: CWE-20: Improper Input Validation in zen-browser desktop
CVE-2026-44658 is a low-severity vulnerability in the zen-browser desktop application prior to version 1. 19. 12b. The issue involves improper input validation (CWE-20) where RSS feed URLs entered by users are validated for http or https schemes, but item links inside the feed are not similarly restricted. These item links are used to create pinned lazy tabs without adequate validation, potentially allowing untrusted URLs to be added as trusted tabs. This vulnerability has been fixed in version 1. 19. 12b.
AI Analysis
Technical Summary
Zen-browser, a Firefox-based desktop browser, had an input validation flaw in versions before 1.19.12b. While user-entered RSS feed URLs were validated to ensure they used http or https schemes, the individual item links within the RSS/Atom feeds were not subjected to the same validation. These item links were mapped into item.url and used by the live-folder manager to create pinned lazy tabs via gBrowser.addTrustedTab(item.url, ...), potentially allowing unvalidated URLs to be treated as trusted. This improper input validation is classified under CWE-20. The issue was addressed and fixed in version 1.19.12b.
Potential Impact
The vulnerability has a low CVSS score of 2.4 and does not impact confidentiality or availability, only integrity to a limited extent. It requires high privileges and user interaction to exploit. There are no known exploits in the wild. The impact is limited to the possibility of untrusted URLs being added as trusted tabs, which could potentially lead to minor integrity issues within the browser environment.
Mitigation Recommendations
This vulnerability is fixed in zen-browser version 1.19.12b. Users and administrators should upgrade to version 1.19.12b or later to remediate this issue. Since no official remediation level is provided beyond the fix, applying the update is the recommended action. No additional mitigation steps are indicated.
CVE-2026-44658: CWE-20: Improper Input Validation in zen-browser desktop
Description
CVE-2026-44658 is a low-severity vulnerability in the zen-browser desktop application prior to version 1. 19. 12b. The issue involves improper input validation (CWE-20) where RSS feed URLs entered by users are validated for http or https schemes, but item links inside the feed are not similarly restricted. These item links are used to create pinned lazy tabs without adequate validation, potentially allowing untrusted URLs to be added as trusted tabs. This vulnerability has been fixed in version 1. 19. 12b.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Zen-browser, a Firefox-based desktop browser, had an input validation flaw in versions before 1.19.12b. While user-entered RSS feed URLs were validated to ensure they used http or https schemes, the individual item links within the RSS/Atom feeds were not subjected to the same validation. These item links were mapped into item.url and used by the live-folder manager to create pinned lazy tabs via gBrowser.addTrustedTab(item.url, ...), potentially allowing unvalidated URLs to be treated as trusted. This improper input validation is classified under CWE-20. The issue was addressed and fixed in version 1.19.12b.
Potential Impact
The vulnerability has a low CVSS score of 2.4 and does not impact confidentiality or availability, only integrity to a limited extent. It requires high privileges and user interaction to exploit. There are no known exploits in the wild. The impact is limited to the possibility of untrusted URLs being added as trusted tabs, which could potentially lead to minor integrity issues within the browser environment.
Mitigation Recommendations
This vulnerability is fixed in zen-browser version 1.19.12b. Users and administrators should upgrade to version 1.19.12b or later to remediate this issue. Since no official remediation level is provided beyond the fix, applying the update is the recommended action. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-07T16:20:08.659Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a021045cbff5d86103d46c2
Added to database: 5/11/2026, 5:22:13 PM
Last enriched: 5/11/2026, 5:37:25 PM
Last updated: 5/11/2026, 6:34:48 PM
Views: 5
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