CVE-2026-49436: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Kovah LinkAce
Description
CVE-2026-49436 is a cross-site scripting (XSS) vulnerability in Kovah LinkAce, a self-hosted link archive. Versions prior to 2.5.7 allow authenticated users to submit URLs with javascript: URIs via the Bulk Link API, which are stored and later rendered without validation. This enables execution of arbitrary JavaScript in users' browsers when clicking such links, potentially leading to cookie and session token theft. The issue is fixed in version 2.5.7.
CVSS v3.1
Score 7.3high
Affected software
Kovah
LinkAce
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
LinkAce versions before 2.5.7 have an XSS vulnerability (CWE-79) in the Bulk Link API endpoint (`POST /api/v2/bulk/links`). The endpoint accepts URLs without format validation, allowing an authenticated user to store a `javascript:` URI. This URI is rendered verbatim as an href attribute in Blade templates, causing arbitrary JavaScript execution in the victim's browser upon clicking the link. This can lead to exfiltration of cookies and session tokens. The vulnerability is addressed in LinkAce version 2.5.7.
Potential Impact
An authenticated attacker can store malicious javascript: URIs that execute arbitrary JavaScript in other users' browsers when clicked. This can result in theft of cookies and session tokens, compromising user accounts. The vulnerability has a CVSS score of 7.3 (high severity), indicating significant confidentiality and integrity impact but no availability impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade LinkAce to version 2.5.7 or later, where the Bulk Link API endpoint properly validates URLs to prevent javascript: URIs from being stored and rendered. This official fix fully mitigates the vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-30T02:43:33.105Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a877787acd9273b492c5e3c
Added to database: 08/20/2026, 21:54:15 UTC
Last enriched: 09/10/2026, 21:02:00 UTC
Last updated: 10/05/2026, 06:48:16 UTC
Views: 56
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