CVE-2026-40986 PUBLISHED

Spring Web Flow JS RemotingHandler renders non-HTML Response as HTML

Assigner: vmware
Reserved: 16.04.2026 Published: 11.06.2026 Updated: 11.06.2026

Spring Web Flow's JavaScript RemotingHandler renders the body of an error response as HTML even when the response is not "text/html", which can result in a scripting attack in the user's browser if the error response from the server contains error details with input reflected from an attacker.

Affected versions: Spring Web Flow 4.0.0; 3.0.0 through 3.0.1; 2.5.0 through 2.5.1.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N
CVSS Score: 4.8

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	None
Privileges Required	Low	Integrity Impact	High
User Interaction	Required	Availability Impact	None

CVSS 3.1

Product Status

Vendor	Spring
Product	Spring Web Flow
Versions	Default: unaffected affected from 4.0.0 to 4.0.1 (excl.) affected from 3.0.0 to 3.0.2 (excl.) affected from 2.5.0 to 2.5.2 (excl.)

References

https://spring.io/security/cve-2026-40986

Problem Types

CWE-79: Improper Neutralization of Input During Web Page Generation (Cross-site Scripting) CWE

Impacts

An attacker who can influence error responses from the server can cause Spring Web Flow's JavaScript RemotingHandler to render attacker-controlled content as HTML in the user's browser.