Nginx UI: Unauthenticated signed-request body staging can exhaust temporary storage

## Summary In Nginx UI versions 2.5.0 through 2.5.x, the node-signature authentication path staged an attacker-controlled request body in a temporary file and synchronized it to disk before validating the body digest and cryptographic signature. An unauthenticated remote client that can reach the API can provide syntactically valid signature metadata and cause storage and I/O consumption before the request is rejected. ## Impact Concurrent malicious requests can consume temporary filesystem capacity, disk I/O, and request-processing resources, potentially disrupting Nginx UI and other services that share the filesystem. The issue affects availability only; it does not bypass authentication and does not provide confidentiality or integrity impact. Deployment-specific reverse-proxy body limits, filesystem quotas, and concurrency limits may reduce practical impact. ## Remediation Upgrade to Nginx UI 2.6.0 or later. The fix authenticates signed request metadata before staging the body and enforces an application-level streaming size limit with cleanup for rejected requests. Fix commit: https://github.com/0xJacky/nginx-ui/commit/8c9b9a1aff218ee6c980d047b750e49da3c46796

Source published

9 Oct 2026 20:57:08 UTC

Source modified

19 Oct 2026 21:40:58 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Publisher rating · HIGH