CVE-2026-42455 (GCVE-0-2026-42455)

Vulnerability from cvelistv5 – Published: 2026-05-08 23:10 – Updated: 2026-05-12 02:19
VLAI
Title
LinkWarden: Stored XSS via Client-Side Archive Upload (Unsanitized HTML served from same origin)
Summary
Linkwarden is a self-hosted, open-source collaborative bookmark manager to collect, organize and archive webpages. In versions 2.14.0 and prior, the archive upload endpoint (POST /api/v1/archives/[linkId]?format=4) accepts HTML files (text/html) without sanitizing JavaScript content. When the archive is later accessed via GET /api/v1/archives/[linkId]?format=4, the HTML is served with Content-Type: text/html from the Linkwarden origin, without any Content-Security-Policy header. This allows arbitrary JavaScript execution in the context of the authenticated Linkwarden sessio. At time of publication, there are no publicly available patches.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-12 02:18 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
linkwarden linkwarden Affected: <= 2.14.0
Create a notification for this product.
Show details on NVD website
To clipboard 

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