Security context

Highlights

Auth Bypass: 1 prior fix. Scrutinize any change in this area.

src/main/java/com/qiniu/util/Auth.java: most-fixed (2 issues). Treat as high-risk during review.

3 high-severity fixes in this history; regressions here are high-impact.

Recurring patterns

Auth Bypass: A race condition in room token generation stemmed from a shared static secret key field ('sk'), allowing concurrent operations to potentially overwrite or use incorrect cryptographic material during Mac initialization. Developers must ensure instance-specific fields are used instead of shared class-level statics for sensitive cryptographic operations.

Authentication Bypass: The use of a static singleton Authorizer dependency to store and retrieve upload tokens in multi-threaded environments created a concurrency vulnerability. This configuration can leak authorization tokens across concurrent upload operations executed by different threads, violating tenant isolation boundaries.

Cryptographic Issues: A failure to validate server-returned block checksums during resumed and stream uploads allowed data to be corrupted or tampered with silently. Explicit CRC32 verification against the local computation is required upon receiving upload responses.