Mobile Advertising ID (IDFA / GAID / AAID)

Detects mobile advertising identifiers - Apple's IDFA and Google's Advertising ID (GAID, also called AAID) - when they appear labelled with an advertising-ID keyword. These IDs are UUIDs in the canonical 8-4-4-4-12 hexadecimal form. Although resettable, advertising IDs are persistent cross-app device identifiers treated as personal data under GDPR and CCPA/CPRA, and their disclosure enables cross-context tracking and re-identification.

Type: regex
Engine: universal
Confidence: medium
Confidence justification: Medium confidence: the UUID body is generic (any v4 UUID matches the hex layout), so detection relies on an explicit advertising-ID label adjacent to the value. The label requirement keeps false positives low, but unlabelled IDFA or GAID values are intentionally not matched.
Jurisdictions: global
Regulations: GDPR, CCPA/CPRA
Frameworks: ISO 27001, ISO 27701
Data categories: pii, device-id
Scope: narrow
Risk rating: 5
Platform compatibility: Purview: Compatible, GCP DLP: Unsupported, Macie: Unsupported, Zscaler: Compatible, Palo Alto: Unsupported, Netskope: Unsupported

Pattern

(?:idfa|gaid|aaid|advertising[\s_-]*id|ad[\s_-]*id)[\s:#=_-]{0,8}[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}(?![0-9a-f-])

Corroborative evidence keywords

advertising id, advertising identifier, IDFA, GAID, AAID, device id, ad tracking, mobile identifier

Proximity: 300 characters

Should match

ad id: 6d92078a-8246-4ba4-ae5b-76104861e7dc — Low-tier probe - labelled candidate without platform context
iOS device IDFA: 97987bca-ae59-4c7d-94ba-ee4f19ab8c21 — Medium-tier probe - labelled identifier plus mobile-platform context
Mobile attribution record for iOS device - IDFA: 12345678-90ab-cdef-1234-567890abcdef; install attribution captured. — High-tier probe - platform context plus attribution record

Should not match

6d92078a-8246-4ba4-ae5b-76104861e7dc — Bare UUID with no advertising-ID label
session id: 6d92078a-8246-4ba4-ae5b — Truncated/non-UUID value behind an unrelated label
reset your advertising identifier in the device privacy settings — Prose mention of an advertising identifier with no value
Public documentation sample payload for an iOS device IDFA: 6d92078a-8246-4ba4-ae5b-76104861e7dc with install attribution. — Public sample contains otherwise high-tier evidence
Template example: mobile attribution record for iOS device IDFA 97987bca-ae59-4c7d-94ba-ee4f19ab8c21. — Template contains otherwise high-tier evidence

Known false positives

Other UUIDs (session tokens, request IDs, correlation IDs) that happen to sit next to the word 'ad' or 'id'. Mitigation: The pattern requires a specific advertising-ID label; tighten the label list further if generic 'ad id' collides in your corpus.