CVE-2026-109290: open-webui · Cross-site Scripting
Affects open-webuiSource CVE Database V5
Public exploit available · CVSS 8.4 High : upgrade to 0.11.4 as a priority.
Data as of 26 Oct 2026, 17:30 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- Proof of concept is public or traded
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-13.
- Patch
- Available – fixed in 0.11.4
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 12 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CISA SSVC: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by VulnCheck
, 2 hours before disclosure
CVE published
on cve.org
, t = 0
CISA SSVC assessment
proof of concept public
, 26 hours after disclosure
In Threat Radar
record ingested
, 14 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA SSVC, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade open-webui to 0.11.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| open-webuiopen-webui | Affected
| Fixed in
|
PyPIopen-webuipkg:pypi/open-webuiOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade open-webui to version 0.11.4 or later, where this vulnerability is fixed. No other mitigations are indicated by the vendor advisory.
Description
Open WebUI versions from 0.11.1 up to but not including 0.11.4 contain a stored cross-site scripting (XSS) vulnerability in the DocxPreview.svelte component. This flaw allows authenticated users to upload specially crafted DOCX files containing malicious HTML or script-scheme hyperlinks. Exploitation can lead to theft of an administrator's session token from local storage and potential takeover of the instance. The vulnerability is fixed in version 0.11.4.