CVE-2025-46572: Passport-wsfed-saml2 allows SAML Authentication Bypass via Signature Wrapping

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.4%, percentile 35: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 35% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes passport-wsfed-saml2 (npm) >= 3.0.5, <= 4.6.3, fixed in 4.6.4. Check your lockfile, including transitive dependencies.

What it is

passport-wsfed-saml2 provides passport strategy for both WS-fed and SAML2 protocol. A vulnerability present starting in version 3.0.5 up to and including version 4.6.3 allows an attacker to impersonate any user during SAML authentication by crafting a SAMLResponse. This can be done by using a valid SAML object that was signed by the configured IdP. Users are affected specifically when the service provider is using passport-wsfed-saml2 and a valid SAML document signed by the Identity Provider can be obtained. Version 4.6.4 contains a fix for the vulnerability.

From the GitHub advisory

Overview This vulnerability allows an attacker to impersonate any user during SAML authentication by crafting a SAMLResponse. This can be done by using a valid SAML object that was signed by the configured IdP.

Am I Affected? You are affected by this SAML Signature Wrapping vulnerability if you are using passport-wsfed-saml2 version 4.6.3 or below, specifically under the following conditions: 1. The service provider is using passport-wsfed-saml2, 2. A valid SAML document signed by the Identity Provider can be obtained.

Fix Upgrade to v4.6.4 or greater.

Weakness type: CWE-287, CWE-347.

Product: passport-wsfed-saml2 (npm) · Assigned by: GitHub_M · Published: 2025-05-06

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Attack requirements: none
• Privileges required: none (no login)
• User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable no, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 0.42% probability of exploitation activity in the next 30 days; percentile 35.

Timeline

• 2025-05-06 — CVE record published by GitHub_M
• 2025-05-06 — GitHub-reviewed advisory GHSA-wjmp-wphq-jvqf published (critical)
• 2025-05-13 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-wjmp-wphq-jvqf github.com
2. CVE.org record CVE-2025-46572 cve.org
3. NVD entry CVE-2025-46572 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com

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