CVE-2025-54369Network attack vector

Authentication bypass via unsigned assertion processing

Published Dec 12, 2025 · Updated May 7, 2026

Improper SAML signature verification in node-saml Node SAML before 5.1.0 allows remote attackers to alter authentication details. validatePostResponseAsync verifies one XML region but passes an assertion taken from the original unsigned response to processValidlySignedAssertionAsync. Exploitation requires a validly signed IdP document and can change the asserted username, causing the relying application to authenticate the wrong identity.

CVSS severity9.3
Critical
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper SAML signature verification in node-saml Node SAML before 5.1.0 allows remote attackers to alter authentication details. validatePostResponseAsync verifies one XML region but passes an assertion taken from the original unsigned response to processValidlySignedAssertionAsync. Exploitation requires a validly signed IdP document and can change the asserted username, causing the relying application to authenticate the wrong identity.

The record

CVE
CVE-2025-54369
Published
Dec 12, 2025
Updated
May 7, 2026
Vendor
node-saml
Product
Node SAML
Classifications
CWE-287, CWE-347, T1606.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 12, 2025CVE publishedPublication date reported by the CVE source.
  2. May 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

node-saml · Node SAMLversion=< 5.1.0

Published CVSS scores

9.3GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-347Improper Verification of Cryptographic Signature
T1606.002Forge Web Credentials: SAML Tokens

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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