Ruby-saml has a SAML authentication bypass due to namespace handling (parser differential)

Description

Summary

Ruby-saml up to and including 1.12.4, there is an authentication bypass vulnerability because of an incomplete fix for CVE-2025-25292. 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. The vulnerability does not affect the version 1.18.0.

Impact

That allows an attacker to be able to execute a Signature Wrapping attack and bypass the authentication

Basic information

Type
reviewed
Severity
critical
Advisory on GitHub
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Repository advisory
Open repository advisory ↗
Source code
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Published (advisory)
2025-12-08 21:30:56 UTC
Updated
2025-12-12 21:53:09 UTC
GitHub reviewed
2025-12-08 21:30:56 UTC
NVD published
2025-12-09

EPSS Score

Score Percentile
0.05% 15.42%

CVSS Scores

Base score Version Severity Vector
9.3 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:H)
High confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.

Identifiers

CWEs

CWE id Name
CWE-347 Improper Verification of Cryptographic Signature

Credits

  • d0ge (reporter)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
rubygems ruby-saml < 1.18.0 1.18.0

References

cvelogic Threat Intelligence