CVE-2025-25293: Ruby SAML allows remote Denial of Service (DoS) with compressed SAML responses
(updated )
ruby-saml is susceptible to remote Denial of Service (DoS) with compressed SAML responses.
Ruby-saml uses zlib to decompress SAML responses in case they’re compressed. It is possible to bypass the message size check with a compressed assertion since the message size is checked before inflation and not after.
References
- about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-released
- github.blog/security/sign-in-as-anyone-bypassing-saml-sso-authentication-with-parser-differentials
- github.com/SAML-Toolkits/ruby-saml
- github.com/SAML-Toolkits/ruby-saml/commit/acac9e9cc0b9a507882c614f25d41f8b47be349a
- github.com/SAML-Toolkits/ruby-saml/commit/e2da4c6dae7dc01a4d9cd221395140a67e2b3eb1
- github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.12.4
- github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.18.0
- github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-92rq-c8cf-prrq
- github.com/advisories/GHSA-92rq-c8cf-prrq
- github.com/omniauth/omniauth-saml/security/advisories/GHSA-hw46-3hmr-x9xv
- github.com/rubysec/ruby-advisory-db/blob/master/gems/ruby-saml/CVE-2025-25293.yml
- nvd.nist.gov/vuln/detail/CVE-2025-25293
- security.netapp.com/advisory/ntap-20250314-0008
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