PT-2026-39675 · Zen Browser · Rdesktop

Published 2026-05-11 · Updated 2026-05-11 · CVE-2026-44659

Mitre

CVSS v3.1

4.7

Medium

Base vector

AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N

Zen is a firefox-based browser. Prior to 1.19.12b, the ZEN Browser incorrectly truncates long hostnames in the address bar and shows only the attacker-controlled prefix of the subdomain, hiding the actual registrable domain (eTLD+1). As a result, an attacker can craft extremely long malicious subdomains that visually imitate trusted brands, and the browser will display only the spoofed prefix, misleading users about the actual origin of the site. This directly compromises the URL bar as a security indicator and creates a phishing/supply-chain attack vector. This vulnerability is fixed in 1.19.12b.

Fix

UI Misrepresentation of Critical Information

Weakness Enumeration

CWE-451

Related Identifiers

CVE-2026-44659

Affected Products

Rdesktop

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-44659 · Security Note
• https://github.com/zen-browser/desktop/security/advisories/GHSA-7p2r-fp29-9w69 · Note