CVE-2026-40988

Unbounded DEFLATE Inflation in SAML 2.0 Service Provider

Published Jun 9, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-m69x-pw9p-7j3q Spring Security SAML2 Service Provider: Unbounded writer inflates the compressed SAML payload into memory (DoS)
References
History
Type Values Removed Values Added
First Time appeared Vmware
Vmware spring Security
CPEs cpe:2.3:a:vmware:spring_security:*:*:*:*:*:*:*:*
Vendors & Products Vmware
Vmware spring Security
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Spring
Spring spring Security
Vendors & Products Spring
Spring spring Security
Type Values Removed Values Added
Description 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.
Title Unbounded DEFLATE Inflation in SAML 2.0 Service Provider
Weaknesses CWE-400
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
vmware
Published
Updated
Jun 27, 2026, 9:22 PM
Reserved
Apr 16, 2026, 2:19 AM
Status
Analyzed
Published
Jun 10, 2026, 12:16 AM
Modified
Jul 23, 2026, 9:10 AM