CVE-2026-45553

Description

NiceGUI is a Python-based UI framework. Prior to version 3.12.0, ui.restructured_text() renders reStructuredText server-side with Docutils without disabling file insertion directives. When a NiceGUI application passes attacker-controlled content to ui.restructured_text(), an attacker can use standard Docutils directives (include, csv-table with :file:, raw with :file:) to read local files readable by the NiceGUI server process. Applications that only pass trusted static strings to ui.restructured_text() are not affected. This issue has been patched in version 3.12.0.

CVSS v3.1 Score

7.5

HIGH

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

EPSS — Exploit Prediction

0.0026

Probability of exploitation

0.17%

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-200 CWE-200

References

Other References

https://github.com/zauberzeug/nicegui/releases/tag/v3.12.0 https://github.com/zauberzeug/nicegui/security/advisories/GHSA-jfrm-rx66-g536

Frequently Asked Questions

What is CVE-2026-45553? +

NiceGUI is a Python-based UI framework. Prior to version 3.12.0, ui.restructured_text() renders reStructuredText server-side with Docutils without disabling file insertion directives. When a NiceGUI application passes attacker-controlled content to ui.restructured_text(), an attacker can use standard Docutils directives (include, csv-table with :file:, raw with :file:) to read local files readable by the NiceGUI server process. Applications that only pass trusted static strings to ui.restructured_text() are not affected. This issue has been patched in version 3.12.0. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-45553? +

CVE-2026-45553 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0026, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-45553? +

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-2025-15625

Unauthenticated user is able to execute arbitrary SQL commands in Sparx Pro Cloud Server database in certain cases.

CVE-2026-22051

StorageGRID (formerly StorageGRID Webscale) versions prior to 11.9.0.13 and 12.0.0.6 are susceptible to a Information Disclosure vulnerability. Successful exploit could …

CVE-2026-54396

An information disclosure vulnerability exists in the MISP AuthKey edit functionality. When a validation error occurs during an AuthKey edit …

CVE-2026-53912

Cerebrate before version 1.37 exposed credential material from self-registration requests. The self-registration workflow stored the registrant’s hashed password in the …

CVE-2026-47177

Quest Bot is an opensource modern Discord Bot built for moderation, utilities and support. Prior to version 1.0.4, a user …

CVE-2026-53725

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. From version …