Cross-source coverage

T1606.002 / ATT&CK

Forge Web Credentials: SAML Tokens

2 rules across 1 source.

From MITRE ATT&CK 19.2

An adversary may forge SAML tokens with any permissions claims and lifetimes if they possess a valid SAML token-signing certificate. The default lifetime of a SAML token is one hour, but the validity period can be specified in the NotOnOrAfter value of the conditions... element in a token. This value can be changed using the AccessTokenLifetime in a LifetimeTokenPolicy. Forged SAML tokens enable adversaries to authenticate across services that use SAML 2.0 as an SSO (single sign-on) mechanism.

An adversary may utilize Private Keys to compromise an organization's token-signing certificate to create forged SAML tokens. If the adversary has sufficient permissions to establish a new federation trust with their own Active Directory Federation Services (AD FS) server, they may instead generate their own trusted token-signing certificate. This differs from Steal Application Access Token and other similar behaviors in that the tokens are new and forged by the adversary, rather than stolen or intercepted from legitimate users.

An adversary may gain administrative Entra ID privileges if a SAML token is forged which claims to represent a highly privileged account. This may lead to Use Alternate Authentication Material, which may bypass multi-factor and other authentication protection mechanisms.

Platforms
SaaS · Windows · IaaS · Office Suite · Identity Provider
Telemetry
azure:signinlogsWinEventLog:SecurityAWS:CloudTrailCloudTrail:SigninWinEventLog:ADFSsaas:accessm365:unifiedm365:exchangem365:sharepoint

How MITRE says to detect it DET0148

Detection Strategy for Forged SAML Tokens

Identity Provider Analytic 0418

Forged SAML tokens can be observed as authentication attempts with valid signatures but missing expected preceding Kerberos or authentication events. Defenders may correlate SAML assertions with absent Event IDs 4769, 1200, or 1202, or tokens issued with abnormal lifetimes, issuers, or claims compared to baseline.

  • azure:signinlogs SAML-based login with anomalous issuer or NotOnOrAfter lifetime
  • WinEventLog:Security EventCode=4769, 1200, 1202

IaaS Analytic 0419

Forged SAML tokens in IaaS environments often manifest as cross-cloud or cross-account authentication without matching STS events. Defenders may see AssumeRole or GetFederationToken API usage without a corresponding SAML assertion log from the trusted IdP.

  • AWS:CloudTrail AssumeRoleWithSAML
  • CloudTrail:Signin SAML login without corresponding IdP authentication log

Windows Analytic 0420

Forged SAML tokens may be used on Windows systems to authenticate to federated apps without normal Kerberos activity. Defenders may detect anomalous event correlation, where access to SaaS/O365 via SAML occurs without prior TGT requests or user logons.

  • WinEventLog:Security EventCode=4624, 4648
  • WinEventLog:ADFS Token issuance events showing anomalous claims or issuers

SaaS Analytic 0421

Forged SAML tokens can appear as SaaS logins where authentication succeeded without MFA, or where tokens contain claims inconsistent with the user profile. Look for concurrent sessions across different geographies with the same SAML assertion ID.

  • saas:access SAML token accepted without preceding login challenge
  • m365:unified Abnormal user claims or unexpected elevated role assignment in SAML assertion

Office Suite Analytic 0422

Forged SAML tokens may be leveraged to access O365 apps such as Outlook or SharePoint. Defenders should monitor for token replay across multiple clients or access attempts to privileged mailboxes without prior interactive login.

  • m365:exchange Mailbox access using SAML token without corresponding MFA event
  • m365:sharepoint File access with forged or anomalous SAML claims

elastic/detection-rules

2 rules
Detection Severity Format
FortiGate FortiCloud SSO Login from Unusual Source Medium Elastic TOML
M365 Identity Unusual SSO Authentication Errors for User Medium Elastic TOML

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