CVE-2026-41851: Spring Framework Denial of Service via Unbounded Cache in SpEL

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-09 · updated 2026-07-23
Weakness: CWE-770

Description

Applications which accept user-supplied Spring Expression Language (SpEL) expressions may be vulnerable to a Denial of Service (DoS) attack if the evaluation of a SpEL expression triggers unbounded cache growth. Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.

Affected products

Spring Framework: from 5.3.0 before 5.3.49; from 6.1.0 before 6.1.28; from 6.2.0 before 6.2.18.1; from 7.0.0 before 7.0.7.1 — fixed in 5.3.49, 6.1.28, 6.2.18.1, 7.0.7.1
Spring Framework: from 7.0.0 before 7.0.7.1; from 6.2.0 before 6.2.18.1; from 6.1.0 before 6.1.28; from 5.3.0 before 5.3.49 — fixed in 7.0.7.1, 6.2.18.1, 6.1.28, 5.3.49

How to fix

Upgrade to a fixed version: Spring Framework 5.3.49, 6.1.28, 6.2.18.1, 7.0.7.1; Spring Framework 7.0.7.1, 6.2.18.1, 6.1.28, 5.3.49. Check the vendor advisory for mitigations.

References

https://spring.io/security/cve-2026-41851

Get alerted when CVE-2026-41851 or the next vulnerability affects your stack