JWT

Detects JSON Web Token candidates with three Base64url segments. A generic encoded-JSON candidate is discovery-only; a standard encoded algorithm header plus encoded JSON payload enforces at medium confidence, and HTTP or session transport binding raises the result to high confidence.

Type

regex

Engine

universal

Confidence

high

Confidence justification

High confidence: structurally constrained pattern with corroborative keyword support reduces false positive rates significantly. Added context gating and exclusion rules improve precision and reduce incidental matches.

Detection quality

Verified

Jurisdictions

global

Regulations

Criminal Code Act 1995 (Cth)

Frameworks

CIS Controls, ISO 27001, NIST CSF, PCI-DSS, SOC 2

Data categories

credentials, security

Scope

specific

Risk rating

8

Platform compatibility

Purview: Compatible, GCP DLP: Compatible, Macie: Compatible, Zscaler: Compatible, Palo Alto: Compatible, Netskope: Compatible

Pattern

\beyJ[A-Za-z0-9_-]{5,}\.[A-Za-z0-9_-]{6,}\.[A-Za-z0-9_-]{3,}\b

Corroborative evidence keywords

api key, api_key, apikey, access key, secret key, private key, auth token, authorization, access token, bearer, conn str, connection string, connectionstring, cookie, credential, database, host, [object Object], oauth, passphrase (+33 more)

Proximity: 300 characters

Should match

• eyJmb28iOiJiYXIifQ.eyJzdWIiOiIxMjMifQ.c2lnbmF0dXJl — Low-tier probe - three encoded segments without a standard alg header
• JWT: eyJhbGciOiJSUzI1NiJ9.eyJpc3MiOiJqb2UifQ.abc123-_def456 — Medium-tier probe - labelled JWT with standard header and encoded payload
• Authorization: Bearer eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0NTY3ODkwIn0.dozjgNryP4J3jVmNHl0w5N_XgL0n3I9PlFUP0THsR8U — High-tier probe - structurally plausible JWT bound to an Authorization header

Should not match

• eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0NTY3ODkwIn0 — Only 2 segments instead of 3
• notJWT.eyJzdWIiOiIxMjM0NTY3ODkwIn0.signature — First segment does not start with eyJ
• eyJ.eyJ.sig — Segments too short to be valid JWT
• Authorization: Bearer eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxIn0.REDACTED — Placeholder signature in a transport-bound JWT
• Documentation example: Authorization: Bearer eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxIn0.c2ln — Documentation quoting a structurally valid JWT must not enforce
• session=YWJjZGVm.Z2hpamts.bW5vcHFy — Sibling three-segment cookie value does not begin with encoded JSON

Known false positives

• Authentication-related terminology in software documentation, security training materials, or system architecture descriptions without actual credentials. Mitigation: Require proximity to credential-specific patterns (API keys, connection strings, tokens) rather than general security terminology.
• Code snippets and configuration examples containing credential-related keywords or placeholder values in developer documentation. Mitigation: Check for common placeholder patterns (example.com, localhost, 0000) and documentation file types to reduce false positives from technical writing.

Collections

• Cloud Credentials & API Keys