CVE-2023-34053: Spring Framework server Web Observations DoS Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-11-28 · updated 2026-06-17

Description

In Spring Framework versions 6.0.0 - 6.0.13, it is possible for a user to provide specially crafted HTTP requests that may cause a denial-of-service (DoS) condition. Specifically, an application is vulnerable when all of the following are true: * the application uses Spring MVC or Spring WebFlux * io.micrometer:micrometer-core is on the classpath * an ObservationRegistry is configured in the application to record observations Typically, Spring Boot applications need the org.springframework.boot:spring-boot-actuator dependency to meet all conditions.

Affected products

Spring Framework: from 6.0.0 before 6.0.14 — fixed in 6.0.14
Spring Framework: from 6.0.0 before 6.0.14 — fixed in 6.0.14

How to fix

Upgrade to a fixed version: Spring Framework 6.0.14; Spring Framework 6.0.14. Check the vendor advisory for mitigations.

References

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