gcdRadar
archive/Patch now/AIR-2026-0308
closedclosed 12 Oct 2026Patch now2 Disclosed vulnerabilityAI

CVE-2026-109298: Open WebUI vulnerable to regex denial of service in search tools

Open WebUI

Open WebUI compiles user-chosen grep patterns with a regex engine susceptible to unbounded expansion of nested repetitions. Authenticated users can block the event loop and exhaust server memory using malicious search strings.

disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why

CVSS
7.1
EPSS
<0.01 · top 59% · 2026-11-13
EPSS scores by FIRST
fix status
Fix status unknown
first report
12 Oct 2026
last update
12 Oct 2026
CVE ids
CVE-2026-109298other records

Timeline · 1

  1. 12 Oct 2026CVE-2026-109298: Open WebUI 0.11.0 before 0.11.4 compiles user-chosen grep patterns for its knowledge and chat file search tools with a regex…

Sources · 1

Advisories and databases

  1. 2026-10-12
    CVE-2026-109298: Open WebUI 0.11.0 before 0.11.4 compiles user-chosen grep patterns for its knowledge and chat file search tools with a regex…
    NVD · nvd.nist.gov/vuln/detail/CVE-2026-109298

Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.

Classification

lane
Patch now
AI role
Attack on AI
categories
Infrastructure vulnerability
severity
2 · Disclosed vulnerability
fix status
Fix status unknown
targets
Framework / tooling
owasp llm top 10
LLM03:2025 Supply Chain
mitre atlas
no technique for these categories
tags
redosopen-webui
dates
happened 12 Oct 2026 · first reported 12 Oct 2026
origin
NVD
Vulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
record
confidence 0.95 · created 2026-10-18 06:33Z · updated 2026-10-18 06:33Z

Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned

Copy a brief

This record as a short Markdown brief, for a ticket, a chat or a coding agent.

the brief as text
# CVE-2026-109298: Open WebUI vulnerable to regex denial of service in search tools

https://gcdradar.vercel.app/incidents/cve-2026-109298-open-webui-vulnerable-to-regex-denial-of-ser · AIR-2026-0308 · closed 2026-10-12

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-10-12
- AI role: Attack on AI
- Products: Open WebUI
- CVE ids: CVE-2026-109298
- CVSS: 7.1

## Summary

Open WebUI compiles user-chosen grep patterns with a regex engine susceptible to unbounded expansion of nested repetitions. Authenticated users can block the event loop and exhaust server memory using malicious search strings.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-10-12: CVE-2026-109298: Open WebUI 0.11.0 before 0.11.4 compiles user-chosen grep patterns for its knowledge and chat file search tools with a regex… (https://nvd.nist.gov/vuln/detail/CVE-2026-109298)

## Sources

- 2026-10-12 NVD: CVE-2026-109298: Open WebUI 0.11.0 before 0.11.4 compiles user-chosen grep patterns for its knowledge and chat file search tools with a regex… https://nvd.nist.gov/vuln/detail/CVE-2026-109298

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.

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