CVE-2026-26266 CRITICAL

CVE-2026-26266: AliasVault affected by Cross-Site Scripting (XSS) via Email HTML Rendering

Vendor Aliasvault
Product aliasvault
Weakness CWE-79 · XSS
Published March 3, 2026
Last update March 4, 2026

CVSS base score

9.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

What the vulnerability does

01Description

AliasVault is a privacy-first password manager with built-in email aliasing. A stored cross-site scripting (XSS) vulnerability was identified in the email rendering feature of AliasVault Web Client versions 0.25.3 and lower. When viewing received emails on an alias, the HTML content is rendered in an iframe using srcdoc, which does not provide origin isolation. An attacker can send a crafted email containing malicious JavaScript to any AliasVault email alias. When the victim views the email in the web client, the script executes in the same origin as the application. No sanitization or sandboxing was applied to email HTML content before rendering. This vulnerability is fixed in 0.26.0.[

Key dates

02Disclosure timeline

March 3, 2026 CVE published
March 4, 2026 Record updated