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TI-2026-30744 Aliases CVE-2026-42455

LinkWarden: Stored XSS via Client-Side Archive Upload (Unsanitized HTML served from same origin)

Priority HIGH 71CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · High · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00458 39th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
linkwardenlinkwardenup to 2.14.0—No fix listedCNA
  • linkwarden Vendorlinkwarden Affected up to 2.14.0 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-42455

References

Other 1

  • TI-2025-31601 Linkwarden Local File Inclusion Vulnerability CVSS 4.0HIGH 8.7
  • TI-2026-32281 LinkWarden: Server-Side Request Forgery (SSRF) in Link Creation via fetchTitleAndHeaders Function CVSS 3.1CRITICAL 9.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences