Cyber Resilience

CVE-2026-45346

XSS in Openwebui Open Webui ≤ 0.6.31

Public PoCXSS
Published
15 May 2026
Modified
17 June 2026
Patch / advisory
View advisory
CVSS Score v4 5.1
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0016 6th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-45346 is a medium-severity Basic XSS (CWE-80) vulnerability in Openwebui Open Webui. Its CVSS base score is 5.1 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Content Injection (T1659); ranked at the 6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

This vulnerability is AI-related — categorised as LLM Application Platforms; in the Other ATLAS/OWASP Terms risk domain.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.6.31, there is a Cross-Site Scripting vulnerability in Open WebUI SVG renderer implementation. This vulnerability is fixed in 0.6.31.

CWE(s)
CWE-80

AI Security AnalysisAI

AI Category
LLM Application Platforms
Risk Domain
Other ATLAS/OWASP Terms
OWASP Top 10 for LLMs 2025
None mapped
Classification Reason
Matched keywords: artificial intelligence, open webui

Related Threats

MITRE ATT&CK Enterprise Techniques

T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
attack.mitre.org →
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
attack.mitre.org →
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-26193Same product: Openwebui Open Webui
CVE-2026-44568Same product: Openwebui Open Webui
CVE-2026-44549Same product: Openwebui Open Webui
CVE-2025-46571Same product: Openwebui Open Webui
CVE-2025-65959Same product: Openwebui Open Webui
CVE-2026-45318Same product: Openwebui Open Webui
CVE-2026-45299Same product: Openwebui Open Webui
CVE-2026-59214Same product: Openwebui Open Webui
CVE-2025-46719Same product: Openwebui Open Webui
CVE-2026-26192Same product: Openwebui Open Webui

Affected Assets

openwebui
open webui
≤ 0.6.31

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.1
  • V1.3.1
  • V1.3.3
  • V1.3.4

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover missing or incorrect neutralization of script tags through targeted XSS test cases.

SI-10 Information Input Validation good match

Input validation explicitly requires checking and neutralizing untrusted web inputs containing script-related characters before they reach a downstream renderer.

SA-8 Security and Privacy Engineering Principles partial match

Secure engineering principles include mandatory output encoding and neutralization of HTML metacharacters to stop injection at the source.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require output encoding and input validation that prevent basic XSS.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches unneutralized script tags before release.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates input validation and output encoding that directly prevent basic XSS.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for neutralization of script-related HTML tags.

A.8.28 Secure coding partial match
prevents

Secure coding standards require proper escaping of <, >, & to block XSS.

A.8.23 Web filtering none match
none

Web filtering can block some reflected XSS payloads at the network edge.

References