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HIGH AI PREVALENCE: HIGH auth.swift.secret.hardcoded-credential

A secret, API key, token, or password is assigned from a hard-coded string literal.

Why AI tools produce this: AI coding tools generate this anti-pattern by default, it appears in a large share of AI-written auth code.

Why this matters

Committed to source control it is one search away from compromise, letting an attacker reuse it against the backing service (CWE-798). AI-generated code inlines the value to make the snippet "just work" and it ships unchanged.

Read the value from the environment, an xcconfig / Info.plist build setting, or a secret store instead, e.g. ProcessInfo.processInfo.environment["API_KEY"], and rotate the leaked secret out of source control.

VULNERABLE
vulnerable.swift
import Foundation

struct Config {
    // ruleid: auth.swift.secret.hardcoded-credential
    let apiKey = "sk_live_51H8xInLqQ2mNpQ"

    // ruleid: auth.swift.secret.hardcoded-credential
    static let clientSecret = "abcdef1234567890XYZ"

    // ruleid: auth.swift.secret.hardcoded-credential
    var password = "s3cr3t_p4ssw0rd_9999"

    // ruleid: auth.swift.secret.hardcoded-credential
    private let jwtSigningToken = "hunter2_signing_key_2026"
}
SAFE
safe.swift
import Foundation

struct Config {
    // Read from the environment, not a literal.
    let apiKey = ProcessInfo.processInfo.environment["API_KEY"]
    let clientSecret = ProcessInfo.processInfo.environment["CLIENT_SECRET"]!

    // Empty / short / placeholder literals are not real secrets.
    let secret = ""
    let token = "abc"
    let apiSecret = "YOUR_SECRET_HERE_XXXX"
    let accessKey = "<replace-with-key-here>"

    // Non-secret names are ignored even with a long literal.
    let username = "maurice.aney.longname"
}

Suppressing this rule

If a finding is a genuine false positive, scope the suppression to the exact line and leave a reason, never disable the rule project-wide. Disable directives are line-scoped by design.

// oauthlint-disable-next-line auth.swift.secret.hardcoded-credential -- <reason>

References

https://developer.apple.com/documentation/security/keychain_services ↗https://cwe.mitre.org/data/definitions/798.html ↗