CVE-2026-42455 (GCVE-0-2026-42455)
Vulnerability from cvelistv5 – Published: 2026-05-08 23:10 – Updated: 2026-05-12 02:19
VLAI
EPSS
VEX
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
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
1 reference
| URL | Tags |
|---|---|
| https://github.com/linkwarden/linkwarden/security… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| linkwarden | linkwarden |
Affected:
<= 2.14.0
|
guessed |
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Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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