CVE-2026-44659: CWE-451: User Interface (UI) Misrepresentation of Critical Information in zen-browser desktop
CVE-2026-44659 is a medium-severity vulnerability in the Zen Browser desktop versions prior to 1.19.12b. The browser incorrectly truncates long hostnames in the address bar, showing only the attacker-controlled prefix of a subdomain and hiding the actual registrable domain. This UI misrepresentation can mislead users into trusting malicious sites that visually imitate legitimate brands, compromising the URL bar as a security indicator and enabling phishing or supply-chain attacks. The issue is fixed in version 1.19.12b. No known exploits are reported in the wild.
AI Analysis
Technical Summary
Zen Browser, a Firefox-based desktop browser, had a vulnerability (CVE-2026-44659) where it truncated long hostnames in the address bar, displaying only the attacker-controlled subdomain prefix and hiding the true registrable domain (eTLD+1). This allowed attackers to craft long malicious subdomains that visually spoof trusted brands, misleading users about the actual site origin. This UI misrepresentation undermines the URL bar's role as a security indicator and creates phishing and supply-chain attack vectors. The vulnerability affects versions prior to 1.19.12b and has a CVSS 3.1 base score of 4.7 (medium severity). The vulnerability is fixed in version 1.19.12b.
Potential Impact
The vulnerability allows attackers to visually spoof the URL in the browser's address bar by hiding the true domain behind a long subdomain prefix. This can lead to phishing attacks or supply-chain attacks by misleading users into trusting malicious sites that appear to be legitimate. There is no direct impact on confidentiality or availability, but the integrity of the URL as a security indicator is compromised.
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 the product is not a cloud service, remediation depends on applying the official browser update. Patch status is confirmed by the vendor's fix in 1.19.12b.
CVE-2026-44659: CWE-451: User Interface (UI) Misrepresentation of Critical Information in zen-browser desktop
Description
CVE-2026-44659 is a medium-severity vulnerability in the Zen Browser desktop versions prior to 1.19.12b. The browser incorrectly truncates long hostnames in the address bar, showing only the attacker-controlled prefix of a subdomain and hiding the actual registrable domain. This UI misrepresentation can mislead users into trusting malicious sites that visually imitate legitimate brands, compromising the URL bar as a security indicator and enabling phishing or supply-chain attacks. The issue is fixed in version 1.19.12b. No known exploits are reported in the wild.
CVSS v3.1
Score 4.7medium
Affected software
pkg:github/zen-browser/desktopRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Zen Browser, a Firefox-based desktop browser, had a vulnerability (CVE-2026-44659) where it truncated long hostnames in the address bar, displaying only the attacker-controlled subdomain prefix and hiding the true registrable domain (eTLD+1). This allowed attackers to craft long malicious subdomains that visually spoof trusted brands, misleading users about the actual site origin. This UI misrepresentation undermines the URL bar's role as a security indicator and creates phishing and supply-chain attack vectors. The vulnerability affects versions prior to 1.19.12b and has a CVSS 3.1 base score of 4.7 (medium severity). The vulnerability is fixed in version 1.19.12b.
Potential Impact
The vulnerability allows attackers to visually spoof the URL in the browser's address bar by hiding the true domain behind a long subdomain prefix. This can lead to phishing attacks or supply-chain attacks by misleading users into trusting malicious sites that appear to be legitimate. There is no direct impact on confidentiality or availability, but the integrity of the URL as a security indicator is compromised.
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 the product is not a cloud service, remediation depends on applying the official browser update. Patch status is confirmed by the vendor's fix in 1.19.12b.
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: 05/11/2026, 17:22:13 UTC
Last enriched: 05/19/2026, 10:55:32 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 125
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