CVE-2026-44659: CWE-451: User Interface (UI) Misrepresentation of Critical Information in zen-browser desktop
CVE-2026-44659 is a vulnerability in the Zen Browser desktop versions prior to 1. 19. 12b where the address bar incorrectly truncates long hostnames, displaying only the attacker-controlled prefix of a subdomain. This misrepresentation hides the actual registrable domain, allowing attackers to craft deceptive URLs that visually mimic trusted brands. This compromises the URL bar as a security indicator and creates a phishing or supply-chain attack vector. The vulnerability has a medium severity score of 4. 7 and is fixed in version 1. 19. 12b.
AI Analysis
Technical Summary
Zen Browser, a Firefox-based desktop browser, improperly truncates long hostnames in the address bar before version 1.19.12b. The browser shows only the initial part of a long subdomain controlled by an attacker, hiding the true registrable domain (eTLD+1). This UI misrepresentation (CWE-451) can mislead users into trusting malicious sites that visually imitate legitimate brands. The vulnerability affects versions prior to 1.19.12b and has been assigned CVE-2026-44659 with a CVSS 3.1 base score of 4.7 (medium severity). The issue is resolved in version 1.19.12b.
Potential Impact
The vulnerability allows attackers to craft URLs with long malicious subdomains that appear trustworthy by hiding the actual domain in the address bar. This undermines the browser's URL bar as a security indicator, increasing the risk of phishing attacks and supply-chain compromises. There is no direct impact on confidentiality or availability, but the integrity of user trust in the URL display is compromised.
Mitigation Recommendations
A fix is available in Zen Browser version 1.19.12b. Users and administrators should update to this version or later to remediate the vulnerability. Since this is a desktop application, manual update or deployment of the patched version is required. Patch status is confirmed by the vendor's versioning information. No additional mitigations are specified.
CVE-2026-44659: CWE-451: User Interface (UI) Misrepresentation of Critical Information in zen-browser desktop
Description
CVE-2026-44659 is a vulnerability in the Zen Browser desktop versions prior to 1. 19. 12b where the address bar incorrectly truncates long hostnames, displaying only the attacker-controlled prefix of a subdomain. This misrepresentation hides the actual registrable domain, allowing attackers to craft deceptive URLs that visually mimic trusted brands. This compromises the URL bar as a security indicator and creates a phishing or supply-chain attack vector. The vulnerability has a medium severity score of 4. 7 and is fixed in version 1. 19. 12b.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Zen Browser, a Firefox-based desktop browser, improperly truncates long hostnames in the address bar before version 1.19.12b. The browser shows only the initial part of a long subdomain controlled by an attacker, hiding the true registrable domain (eTLD+1). This UI misrepresentation (CWE-451) can mislead users into trusting malicious sites that visually imitate legitimate brands. The vulnerability affects versions prior to 1.19.12b and has been assigned CVE-2026-44659 with a CVSS 3.1 base score of 4.7 (medium severity). The issue is resolved in version 1.19.12b.
Potential Impact
The vulnerability allows attackers to craft URLs with long malicious subdomains that appear trustworthy by hiding the actual domain in the address bar. This undermines the browser's URL bar as a security indicator, increasing the risk of phishing attacks and supply-chain compromises. There is no direct impact on confidentiality or availability, but the integrity of user trust in the URL display is compromised.
Mitigation Recommendations
A fix is available in Zen Browser version 1.19.12b. Users and administrators should update to this version or later to remediate the vulnerability. Since this is a desktop application, manual update or deployment of the patched version is required. Patch status is confirmed by the vendor's versioning information. No additional mitigations are specified.
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: 6a021045cbff5d86103d46c5
Added to database: 5/11/2026, 5:22:13 PM
Last enriched: 5/11/2026, 5:37:11 PM
Last updated: 5/11/2026, 6:38:19 PM
Views: 5
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