---
id: CVE-2026-40988
title: >-
  An application using spring-security-saml2-service-provider and the REDIRECT
  binding for SAML 2.0 Login or Logout may be vulnerable to a denial of service
  by way of an unbounded writer that inflates the compressed SAML payload into
  memor…
summary: >-
  An application using spring-security-saml2-service-provider and the REDIRECT
  binding for SAML 2.0 Login or Logout may be vulnerable to a denial of service
  by way of an unbounded writer that inflates the compressed SAML payload into
  memor…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-400
vendor: vmware
product: spring_security
affected:
  - 'spring_security >= 5.7.0, < 5.7.24'
  - 'spring_security >= 5.8.0, < 5.8.26'
  - 'spring_security >= 6.3.0, < 6.3.17'
  - 'spring_security >= 6.4.0, < 6.4.17'
  - 'spring_security >= 6.5.0, < 6.5.10.2'
  - 'spring_security >= 7.0.0, < 7.0.5.1'
patched:
  - spring_security 7.0.5.1
published: '2026-06-10'
updated: '2026-07-17'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-40988'
references:
  - url: 'https://spring.io/security/cve-2026-40988'
    label: security@vmware.com
tags:
  - nvd
epss: 0.00331
epssPercentile: 0.26517
ingestedAt: '2026-07-17T21:16:23.968Z'
---

## Overview

An application using spring-security-saml2-service-provider and the REDIRECT binding for SAML 2.0 Login or Logout may be vulnerable to a denial of service by way of an unbounded writer that inflates the compressed SAML payload into memory.

Affected versions:
Spring Security 5.7.0 through 5.7.23; 5.8.0 through 5.8.25; 6.3.0 through 6.3.16; 6.4.0 through 6.4.16; 6.5.0 through 6.5.10; 7.0.0 through 7.0.5.

## Affected

- `spring_security >= 5.7.0, < 5.7.24`
- `spring_security >= 5.8.0, < 5.8.26`
- `spring_security >= 6.3.0, < 6.3.17`
- `spring_security >= 6.4.0, < 6.4.17`
- `spring_security >= 6.5.0, < 6.5.10.2`
- `spring_security >= 7.0.0, < 7.0.5.1`

## Remediation

Upgrade past the affected range:

- `spring_security 7.0.5.1`