CVE-2026-44658

Zen Browser: RSS Live-Folder Item URLs Are Not Scheme-Restricted Before Trusted Tab Creation

Published: May 11, 2026Updated: May 13, 2026 Sources: CVE List NVDCWE-20

2.4LOW

Description

Zen is a firefox-based browser. Prior to 1.19.12b, RSS feed URLs entered by the user are validated to http: or https: in promptForFeedUrl, but item links inside the feed are not subject to the same restriction. The provider maps each RSS/Atom item link into item.url, filters only for presence and date, and returns the item list. The live-folder manager later creates pinned lazy tabs from these values with gBrowser.addTrustedTab(item.url, ...). This vulnerability is fixed in 1.19.12b.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:HPrivileges Required

High

UI:RUser Interaction

Required

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-20

Affected Products

zen-browser

oss-projectaka desktop

desktopMixed

Consumer Software / browser

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://github.com/zen-browser/desktop/security/advisories/GHSA-cc9c-mmmf-c5j6

github.com

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