CVE-2026-107805: 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
Other sources
Nginx UI is a web user interface for the Nginx web server. From 2.5.0 until 2.6.0, the node-signature authentication path performs temporary file staging of an attacker-controlled request body and synchronizes it before validating the body digest and cryptographic signature. An unauthenticated remote client that can reach the API and provide syntactically valid signature metadata can consume temporary filesystem capacity, disk input and output, and request-processing resources before rejection. The issue affects availability and does not bypass authentication or provide confidentiality or integrity impact. This issue is fixed in version 2.6.0.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
go/github.com/0xJacky/Nginx-UIto a version that resolves this vulnerability.Fixed in 1.9.10-0.20260901043436-8c9b9a1aff21 - Upgrade
Upgrade
Nginx UIto a version that resolves this vulnerability.Fixed in 2.6.0 - Compensating control
Apply deployment-specific reverse-proxy request-body limits, filesystem quotas, and concurrency limits to reduce the impact of malicious requests.
Event History
Frequently Asked Questions
Which deployments are exposed?
Nginx UI versions from 2.5.0 until 2.6.0 are affected. Exposure requires that an unauthenticated remote client can reach the API endpoint using the node-signature authentication path.
What does an attacker need to trigger the resource consumption?
The attacker does not need credentials, but must provide syntactically valid signature metadata. Request-body staging and synchronization occur before the body digest and cryptographic signature are validated.
Does successful exploitation expose or alter protected data?
No. The reported impact is availability only: temporary filesystem capacity, disk I/O, and request-processing resources can be consumed before the request is rejected; authentication is not bypassed.