CVE-2026-40976
CRITICALDescription
In certain circumstances, Spring Boot's default web security is ineffective allowing unauthorized access to all endpoints. For an application to be vulnerable, it must: be a servlet-based web application; have no Spring Security configuration of its own and rely on the default web security filter chain; depend on spring-boot-actuator-autoconfigure; not depend on spring-boot-health. If any of the above does not apply, the application is not vulnerable. Affected: Spring Boot 4.0.0–4.0.5; upgrade to 4.0.6 or later per vendor advisory.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 39% of all known CVEs.
References
Related Vulnerabilities
Other CWE-862 (Missing Authorization) vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2021-39226 | Critical | 9.8 | 100% | KEV | Fix |
| CVE-2022-0543 | Critical | 10.0 | 99% | KEV | Fix |
| CVE-2021-21978 | Critical | 9.8 | 99% | - | Fix |
| CVE-2023-52163 | High | 8.8 | 97% | KEV | - |
| CVE-2022-1329 | High | 8.8 | 93% | - | - |
| CVE-2023-6875 | Critical | 9.8 | 90% | - | - |
Common questions
How do I fix CVE-2026-40976?
Upgrade spring boot to 4.0.6 or later.
Is CVE-2026-40976 being actively exploited?
Not that we know of. CVE-2026-40976 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.49% is the estimated probability that it will be exploited in the next 30 days. That is higher than 39% of all scored CVEs.
How severe is CVE-2026-40976?
CVE-2026-40976 has a CVSS v3 base score of 9.1, rated critical. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-40976 affect?
Published advisories record a fix for spring boot (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-40976
Markdown
[](https://tridentstack.com/cve/CVE-2026-40976)HTML
<a href="https://tridentstack.com/cve/CVE-2026-40976"><img src="https://tridentstack.com/cve/badge/CVE-2026-40976.svg" alt="CVE-2026-40976"></a>Find and fix vulnerabilities across your fleet
TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-07-24.