CVE-2026-45331

Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, validate_url() in backend/open_webui/retrieval/web/utils.py calls validators.ipv6(ip, private=True), but the validators library does NOT implement the private keyword for IPv6 — the call raises a ValidationError (which is falsy in a boolean context), so every IPv6 address passes the filter. In addition, IPv4-mapped IPv6 (::ffff:10.0.0.1) bypasses the IPv4 check entirely, and several reserved IPv4 ranges (0.0.0.0/8, 100.64.0.0/10, 192.0.0.0/24, etc.) are not blocked. This vulnerability is fixed in 0.9.0.

Overview

State: PUBLISHED
Assigner (CNA): GitHub_M
CVSS severity: HIGH
CVSS score: 8.5 / 10
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
Effective score: 8.5 / 10 HIGH source: CNA overview
CWE(s): CWE-918
Reserved: 2026-05-11
Published: 2026-05-15 21:22 UTC
Last updated: 2026-05-16 00:21 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/45xxx/CVE-2026-45331.json
Linked Threat: CVE-2026-45331 — Open WebUI: Full SSRF Vulnerability in the RAG Web Search Feature

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-05-15 20:16:48 UTC
NVD last modified: 2026-05-19 03:06:35 UTC
NVD CVSS v3.1: 8.5 / 10 HIGH source: security-advisories@github.com
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
Exploitability subscore: 3.1 / 10
Impact subscore: 4.7 / 10
EPSS score: 0.0001 (probability of exploitation in next 30 days)
EPSS percentile: 2.19% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-30611
Assigner: GitHub_M
Published: May 15, 2026, 7:22:58 PM
Updated: May 15, 2026, 10:21:52 PM
EUVD base score (CVSS 3.1): 8.5 / 10
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N
EUVD-reported EPSS: 0.0100
Vendors: open-webui
Products: open-webui (< 0.9.0)
Aliases: GHSA-4v7r-f4w8-8972

ENISA description: Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, validate_url() in backend/open_webui/retrieval/web/utils.py calls validators.ipv6(ip, private=True), but the validators library does NOT implement the private keyword for IPv6 — the call raises a ValidationError (which is falsy in a boolean context), so every IPv6 address passes the filter. In addition, IPv4-mapped IPv6 (::ffff:10.0.0.1) bypasses the IPv4 check entirely, and several reserved IPv4 ranges (0.0.0.0/8, 100.64.0.0/10, 192.0.0.0/24, etc.) are not blocked. This vulnerability is fixed in 0.9.0.

EUVD references (1)

https://github.com/open-webui/open-webui/security/advisories/GHSA-4v7r-f4w8-8972

Affected products (1)

Vendor	Product	Versions	Platforms
open-webui	open-webui	`< 0.9.0` (affected)	—

Affected products — CPE 2.3 (1) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

https://github.com/open-webui/open-webui/security/advisories/GHSA-4v7r-f4w8-8972 x_refsource_CONFIRM

MITRE references (1) cveawg.mitre.org

Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.

https://github.com/open-webui/open-webui/security/advisories/GHSA-4v7r-f4w8-8972 x_refsource_CONFIRM

Web references (3)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

https://nvd.nist.gov/vuln/detail/CVE-2026-45331 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-45331 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org

NVD-tagged references (2)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/open-webui/open-webui/security/advisories/GHSA-4v7r-f4w8-8972 security-advisories@github.com ExploitMitigationVendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-4v7r-f4w8-8972 134c704f-9b21-4f2e-91b3-4a467353bcc0 ExploitMitigationVendor Advisory

Indicators (5)

IOCs linked to the auto-promoted Threat row.

Type	Value	VirusTotal	Attached
ipv4	`0.0.0.0`	2026-05-31 00:18 UTC)">not flagged	2026-05-18 21:17 UTC
domain	`utils.py`	no local data UrlVoid 0 / 35	2026-05-18 21:17 UTC
ipv4	`10.0.0.1`	2026-05-22 02:41 UTC)">not flagged	2026-05-18 21:17 UTC
ipv4	`100.64.0.0`	2026-05-22 02:37 UTC)">not flagged	2026-05-18 21:17 UTC
ipv4	`192.0.0.0`	no local data	2026-05-18 21:17 UTC

Remediations (17)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

CISA Warns of Exploited Microsoft Defender 0-Day Flaws

web:cyberpress.org

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .

2026-05-22 17:24 UTC
CISA Adds One Known Exploited Vulnerability to Catalog

web:www.cisa.gov

Linux Kernel Incorrect Resource Transfer Between Spheres Vulnerability This type of vulnerability is a frequent attack vector for malicious cyber actors and poses significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and ...

2026-05-22 17:24 UTC
Microsoft Patch Tuesday March 2026 - 78 Vulnerabilities Fixed ...

web:cybersecuritynews.com

Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...

2026-05-22 17:24 UTC
Microsoft and Adobe Patch Tuesday, April 2026 Security Update Review

web:blog.qualys.com

With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.

2026-05-22 17:24 UTC
CVE-2026-46333 (ssh-keysign-pwn) Linux kernel vulnerability ... - Ubuntu

web:ubuntu.com

An information disclosure security vulnerability in the Linux kernel was publicly disclosed on May 15th, 2026 . The vulnerability was reported by Qualys and fixed in the mainline Linux kernel tree. A proof-of-concept exploit was published soon after public disclosure. The ID CVE - 2026 -46333 was assigned, but the vulnerability is also referr […]

2026-05-22 17:24 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-05-22 17:24 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-22 17:24 UTC
Critical Patches Issued for Microsoft Products, April 14, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-05-22 04:23 UTC
Linux faces its largest security threat in years—here's how to deal ...

web:www.howtogeek.com

Here's the list of mitigation solutions available as we go to publication: Ubuntu Red Hat Enterprise Linux SUSE The Red Hat team warns that there may be a "performance impact" for any task that requires Linux kernel cryptograpic features, so you might notice the effects until a patch lets you restore the relevant processes.

2026-05-22 04:23 UTC
CVE-2026-45331 - Open WebUI - Broken Access Control | LeakyCreds

web:www.leakycreds.com

Technical analysis of CVE-2026-45331 including high severity, CVSS 8.5, impact assessment, and exploitation activity. Updated vulnerability intelligence by LeakyCreds.

2026-05-22 04:23 UTC
US government warns of severe CopyFail bug affecting major versions of ...

web:techcrunch.com

A severe security vulnerability affecting almost every version of the Linux operating system has caught defenders off-guard and scrambling to patch after security researchers publicly released ...

2026-05-22 04:23 UTC
Microsoft and Adobe Patch Tuesday, May 2026 Security Update Review

web:blog.qualys.com

May 2026's Patch Tuesday arrives with Microsoft addressing a fresh set of vulnerabilities across its ecosystem, reinforcing the ongoing need for timely patching in an increasingly threat-heavy…

2026-05-22 04:23 UTC
Microsoft Patch Tuesday May 2026 - 120 Vulnerabilities Fixed, Including ...

web:cybersecuritynews.com

Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.

2026-05-22 04:23 UTC
Nvd - Cve-2026-45331

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-22 04:23 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-22 04:23 UTC
Copy Fail Linux Kernel Vulnerability Now Patched in Debian, Ubuntu, and ...

web:9to5linux.com

The Copy Fail Linux kernel security vulnerability that could allow a local user to elevate privileges to the root user has now been patched.

2026-05-22 04:23 UTC
CVE-2026-45331: Open WebUI SSRF Vulnerability in RAG Web Search Feature

web:vulert.com

CVE-2026-45331 details an SSRF vulnerability in Open WebUI, allowing unauthorized access to internal services. Update to version 0.9.0 or later to mitigate risks.

2026-05-22 04:23 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-45331.json.

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