CVE-2026-87012: open webui — Exploit & Fix

Description

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, backend/open_webui/models/calendar.py stored the calendar event meta.alert_minutes value without type validation and the shared upcoming-event scheduler compared that value numerically. An authenticated user with the calendar permission could store a non-numeric alert_minutes value that raised an exception and aborted the instance-wide alert pass, suppressing all users' reminders while the event remained in the lookahead window. This issue is fixed in version 0.11.1.

Is your site exposed to CVE-2026-87012?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

EPSS — Exploit Prediction

0.0028

Probability of exploitation

0.20%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-754 CWE-754

CWE-1287 CWE-1287

Affected Products

Vendor	Product	Versions
openwebui	open_webui	0.9.0 — 0.11.1

References

Advisories & Patches

https://github.com/open-webui/open-webui/commit/abc69000b33b4894fbd97fc2c962139cf9a8d784 https://github.com/open-webui/open-webui/pull/28790 https://github.com/open-webui/open-webui/security/advisories/GHSA-v39v-59xw-j98g

Exploits

https://github.com/open-webui/open-webui/security/advisories/GHSA-v39v-59xw-j98g

Other References

https://github.com/open-webui/open-webui/releases/tag/v0.11.1

Frequently Asked Questions

What is CVE-2026-87012? +

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, backend/open_webui/models/calendar.py stored the calendar event meta.alert_minutes value without type validation and the shared upcoming-event scheduler compared that value numerically. An authenticated user with the calendar permission could store a non-numeric alert_minutes value that raised an exception and aborted the instance-wide alert pass, suppressing all users' reminders while the event remained in the lookahead window. This issue is fixed in version 0.11.1. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2026-87012? +

CVE-2026-87012 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0028, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-87012? +

CVE-2026-87012 affects products from openwebui, specifically: open_webui. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-87012? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-0667

CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability that could cause arbitrary code execution, denial of service and loss …

CVE-2026-35225

An unauthenticated remote attacker is able to exhaust all available TCP connections in the CODESYS EtherNet/IP adapter stack, preventing legitimate …

CVE-2025-0112

A problem with a detection mechanism in the Palo Alto Networks Cortex XDR agent on Windows devices enables a user …

CVE-2025-0116

A Denial of Service (DoS) vulnerability in Palo Alto Networks PAN-OS software causes the firewall to unexpectedly reboot when processing …

CVE-2025-0128

A denial-of-service (DoS) vulnerability in the Simple Certificate Enrollment Protocol (SCEP) authentication feature of Palo Alto Networks PAN-OS® software enables …

CVE-2025-0129

An improper exception check in Palo Alto Networks Prisma Access Browser allows a low privileged user to prevent Prisma Access …

CVE-2026-87012