CVE-2026-44659 Zen Browser Mac - Address Bar Spoofing via Long Subdomain
Attackers can spoof the address bar using long subdomains to mislead users about the site's origin, facilitating phishing attacks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-44659?
CVE-2026-44659 is a medium-severity vulnerability in zen-browser desktop, published on 11 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-451
Which versions are affected by CVE-2026-44659?
How do I fix CVE-2026-44659?
No fix has been published for CVE-2026-44659 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-44659 being exploited?
There is no known exploitation of CVE-2026-44659 in the wild and no public exploit code.
Sources
Also known as GHSA-7p2r-fp29-9w69.