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CVE-2026-123802

8.1 highEPSS 0.3%

High (8.1) in supertokens supertokens-core. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.

On this page
SuperTokens Core is an open source authentication server. From 11.3.0 until 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, and 12.3.1, a licensed deployment with a configured SAML client can authenticate an identity from an assertion that did not satisfy the audience check. When the identity provider uses assertion-level signing, an attacker who has a still-valid IdP-signed assertion naming the victim for any audience and the attacker's own valid assertion for the target audience can combine them because validateSamlResponseAudience accepts an audience from one assertion while extractAllClaims takes the final NameID and attributes from another; response-level signing does not expose this multi-assertion variant. Independently, an assertion from an identity provider configured for the target deployment but issued to another SuperTokens deployment using the shared default saml_sp_entity_id can satisfy the target's audience check. Successful exploitation authenticates the attacker as the victim IdP user. This issue is fixed in versions 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, and 12.3.1.

Severity

CVSS 3.1

8.1 high
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS
0.3% estimated probability of exploitation activity in the next 30 days; 23rd percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
CWEs
CWE-287 Improper Authentication
CWE-345 Insufficient Verification of Data Authenticity
CWE-1220 Insufficient Granularity of Access Control
OWASP Top 10
A07:2025 Authentication Failures, A08:2025 Software or Data Integrity Failures
Published
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
supertokens-core>= 11.3.0, < 11.3.8
supertokens-core>= 11.4.0, < 11.4.8
supertokens-core>= 12.0.0, < 12.0.11
supertokens-core>= 12.1.0, < 12.1.2
supertokens-core>= 12.2.0, < 12.2.1
supertokens-core>= 12.3.0, < 12.3.1

Attack patterns (CAPEC)

  • CAPEC-1 Accessing Functionality Not Properly Constrained by ACLs Likelihood: High · Severity: High
  • CAPEC-180 Exploiting Incorrectly Configured Access Control Security Levels Likelihood: High · Severity: Medium
  • CAPEC-22 Exploiting Trust in Client Likelihood: High · Severity: High
  • CAPEC-57 Utilizing REST's Trust in the System Resource to Obtain Sensitive Data Likelihood: Medium · Severity: Very High
  • CAPEC-94 Adversary in the Middle (AiTM) Likelihood: High · Severity: Very High
  • CAPEC-114 Authentication Abuse Severity: Medium
  • CAPEC-115 Authentication Bypass Severity: Medium
  • CAPEC-151 Identity Spoofing Likelihood: Medium · Severity: Medium
  • CAPEC-194 Fake the Source of Data Severity: Medium
  • CAPEC-593 Session Hijacking Likelihood: High · Severity: Very High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-287, CWE-345 (12).

References

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