CVE-2026-40988Unbounded DEFLATE Inflation in SAML 2.0 Service Provider
- 7.5HighCVSS base score
- 0.33%Exploitation in 30 daysEPSS · top 73% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By vmware
- 54 days later
· 54 days later
Published
- 18 days later
· 18 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| vmwareCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Analyzed | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.33% · top 73% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
- affected 5.7.0 – < 5.7.24
- affected 5.8.0 – < 5.8.26
- affected 6.3.0 – < 6.3.17
- affected 6.4.0 – < 6.4.17
- affected 6.5.0 – < 6.5.10.2
- affected 7.0.0 – < 7.0.5.1
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenorg.springframework.security:spring-security-saml2-service-providerGHSA-m69x-pw9p-7j3q (opens in a new tab)
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-35883 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-m69x-pw9p-7j3q (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-40988)Record last updated .