Critical severity · published Mar 12, 2025
CVE-2025-25291
ruby-saml vulnerable to SAML authentication bypass due to DOCTYPE handling (parser differential)
9.8
CVSS
21%
EPSS
No
On KEV
Description
ruby-saml provides security assertion markup language (SAML) single sign-on (SSO) for Ruby. An authentication bypass vulnerability was found in ruby-saml prior to versions 1.12.4 and 1.18.0 due to a parser differential. ReXML and Nokogiri parse XML differently; the parsers can generate entirely different document structures from the same XML input. That allows an attacker to be able to execute a Signature Wrapping attack. This issue may lead to authentication bypass. Versions 1.12.4 and 1.18.0 fix the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)21.0% · higher than 98% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RU
ruby-saml · SAML-Toolkits
< 1.12.4; >= 1.13.0, < 1.18.0 · source: vendor, NVD
OS
Omniauth Saml · Omniauth
before 1.10.6; 2.0.0 before 2.1.3; 2.2.0 before 2.2.3 · source: NVD
ST
Storagegrid · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-25291
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-25291
Patch
https://about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-released
Exploit
https://github.blog/security/sign-in-as-anyone-bypassing-saml-sso-authentication-with-parser-differentials
Patch
https://github.com/SAML-Toolkits/ruby-saml/commit/e76c5b36bac40aedbf1ba7ffaaf495be63328cd9
Patch
https://github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97
Release Notes
https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.12.4
Release Notes
https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.18.0
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