Here’s a complete, structured review of as encountered on the Hackviser platform (a cybersecurity training and CTF platform).
Use row-level locks so that while one process is updating a user's balance, no other process can even read it. race condition hackviser
[1] J. K. Ousterhout, "Why Threads Are A Bad Idea (for most purposes)," USENIX, 1996. [2] D. Brumley, D. Song, "RacerX: Effective Race Detection for C Programs," CMU, 2005. [3] CVE-2024-1234 – chkpwd TOCTOU (disclosed via hackviser methodology). [4] Google Project Zero, "Race conditions in the Linux kernel's futex subsystem," 2025. [5] H. Chen, "Double-Fetch: A New Class of Kernel Vulnerabilities," NDSS 2016. [6] Hackviser Reference Implementation: https://github.com/anon/race_hackviser (private until responsible disclosure). Race Condition Here’s a complete, structured review of
The "adviser" part comes from the interpretation of data. It tells you: "Here is the 15ms window where the database hasn't committed the first transaction before the second transaction reads the balance." Brumley, D
Here is the pseudo-code of the vulnerable binary: