CVE-2025-25293

ruby-saml vulnerable to Remote Denial of Service (DoS) with compressed SAML responses

ruby-saml provides security assertion markup language (SAML) single sign-on (SSO) for Ruby. Prior to versions 1.12.4 and 1.18.0, 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. This issue may lead to remote Denial of Service (DoS). Versions 1.12.4 and 1.18.0 fix the issue.

Affected

SAML-Toolkits · ruby-saml

CVSS v4.0 GITHUB

7.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v4.0 GitHub

7.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P

CVSS v3.1 NVD

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

1.53% chance of exploitation in the next 30 days, 74th percentile

Published

2025-03-12

Updated

2025-11-03

Proof-of-concept exploits (1)

• https://github.blog/security/sign-in-as-anyone-bypassing-saml-sso-authentication-with-par…

Security advisories

• SAML-Toolkits/ruby-saml/security/advisories/GHSA-92rq-c8cf-prrq
• omniauth/omniauth-saml/security/advisories/GHSA-hw46-3hmr-x9xv
• https://security.netapp.com/advisory/ntap-20250314-0008
• https://securitylab.github.com/advisories/GHSL-2024-355_ruby-saml
• advisories/GHSA-92rq-c8cf-prrq
• https://about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-released
• SAML-Toolkits/ruby-saml/commit/acac9e9cc0b9a507882c614f25d41f8b47be349a

References

• CVE Record
• NVD entry