CVE-2026-41840 Spring Framework Denial of Service via Multipart Requests in WebFlux
Attackers can cause denial of service in Spring WebFlux applications by sending malicious multipart requests, requiring developers to upgrade the framework.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-41840?
CVE-2026-41840 is a medium-severity denial of service vulnerability in Vmware Spring Framework, published on 9 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Spring WebFlux applications are vulnerable to Denial of Service (DoS) attacks when processing multipart requests. 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.
Weakness: CWE-401
Which versions are affected by CVE-2026-41840?
8 open source packages ship an affected version, including org.springframework:spring-webflux. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.springframework:spring-webflux Maven | All versions to 5.3.39 | None |
org.springframework:spring-webflux Maven | All versions to 5.3.39 | None |
org.springframework:spring-webflux Maven | From 6.1.0 to 6.1.21 | None |
org.springframework:spring-webflux Maven | From 6.1.0 to 6.1.21 | None |
org.springframework:spring-webflux Maven | From 6.2.0 | 6.2.19 |
org.springframework:spring-webflux Maven | From 6.2.0 | 6.2.19 |
2 more packages
org.springframework:spring-webflux Maven | From 7.0.0 | 7.0.8 |
org.springframework:spring-webflux Maven | From 7.0.0 | 7.0.8 |
Products include Vmware Spring Framework.
How do I fix CVE-2026-41840?
Upgrade org.springframework:spring-webflux to a fixed version for your release line: 6.2.19 or 7.0.8.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-41840 being exploited?
There is no known exploitation of CVE-2026-41840 in the wild and no public exploit code.
Other vulnerabilities in Vmware Spring Framework
- CVE-2026-47884 Spring Framework Improper Path Limitation in XsltView
- CVE-2026-47890 Spring Framework Server Sent Event stream corruption while rendering fragments
- CVE-2026-47891 Spring Framework maxInMemorySize Bypassed in Jaxb2Decoder
- CVE-2026-47892 Spring Framework Header Predicate Bypass in WebFlux Functional Endpoints
- CVE-2026-59313 Server Sent Event stream corruption in Spring MVC functional web framework
Sources
Also known as CLEANSTART-2026-OG97140, CLSA-2026-1789218209, CLSA-2026-1790082496, CLSA-2026-1790082526, DEBIAN-CVE-2026-41840, ECHO-a68b-c591-23bc and 4 more.