CVE-2026-90583
A security flaw has been discovered in kagisearch smallweb up to 0ecb9c48edbf98dc7e934b54fbac43869e64b4cf. The affected element is the function index of the file app/sw.py of the component Query String Rendering. Performing a manipulation of the argument qs results in cross site scripting. The attack is possible to be carried out remotely. This product adopts a rolling release strategy to maintain continuous delivery. Therefore, version details for affected or updated releases cannot be specified. The patch is named 00b68144e583f20a6b67e29cf01bc07f57979ffb. It is recommended to apply a patch to fix this issue. Exploitability requires a raw HTTP request carrying unencoded double-quote characters in the query string - Werkzeug's request.query_string returns the raw request-target, and ordinary browsers percent-encode " as %22, so the payload only lands via netcat/curl-style raw sockets.
What this means for your business
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N- CVSS v4
- 5.3
- Weakness
- CWE-79
- Assigned by
- cna@vuldb.com
Dates
- Published
- 2026-09-13
- Last modified
- 2026-09-15
- Sources
- NVD
References
- https://github.com/kagisearch/smallweb/
- https://github.com/kagisearch/smallweb/commit/00b68144e583f20a6b67e29cf01bc07f57979ffb
- https://github.com/kagisearch/smallweb/issues/854
- https://vuldb.com/cve/CVE-2026-90583
- https://vuldb.com/submit/913779
- https://vuldb.com/vuln/403168
- https://vuldb.com/vuln/403168/cti