CVE-2026-26266
Stored XSS in AliasVault Web Client Email Rendering
Publication date: 2026-03-03
Last updated on: 2026-03-05
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| aliasvault | aliasvault | to 0.26.0 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability is a stored cross-site scripting (XSS) issue in the AliasVault Web Client versions 0.25.3 and lower. It occurs in the email rendering feature where received emails on an alias are displayed. The HTML content of these emails is rendered inside an iframe using the srcdoc attribute, which does not provide origin isolation.
Because there is no sanitization or sandboxing of the email HTML content before rendering, an attacker can send a specially crafted email containing malicious JavaScript to any AliasVault email alias. When the victim views this email in the web client, the malicious script executes with the same origin as the application, potentially compromising the user's session or data.
This vulnerability is fixed in version 0.26.0 of AliasVault.
How can this vulnerability impact me? :
This vulnerability can have severe impacts because it allows an attacker to execute malicious JavaScript in the context of the AliasVault web application.
- An attacker could steal sensitive information such as passwords or session tokens.
- The attacker could perform actions on behalf of the victim within the application.
- It could lead to a complete compromise of the user's account or data confidentiality.
The CVSS v3.1 base score of 9.3 indicates a critical severity with high impact on confidentiality and integrity.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade AliasVault Web Client to version 0.26.0 or later, where the issue has been fixed.