CVE-2026-44659
Zen Browser Mac - Address Bar Spoofing via Long Subdomain
No known exploitation. EPSS puts it in the 18th percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 18th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
3 events over 2 days, from the signal feeds we watch.
- Record updated
- Publishedweakness classified
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
Scored 4.7 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
Sources
References in the record
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