Replace rand() with random_bytes() for SQL placeholder generation#4
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flightlesstux wants to merge 1 commit intomasterfrom
Open
Replace rand() with random_bytes() for SQL placeholder generation#4flightlesstux wants to merge 1 commit intomasterfrom
flightlesstux wants to merge 1 commit intomasterfrom
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getCaseSensitiveValue() and getCaseSensitiveValues() used rand() to generate unique named placeholder suffixes for CakePHP's query binder. rand() is a pseudo-random function seeded from a low-entropy source; under concurrent load or on platforms with a weak PRNG, it can produce collisions that cause the query binder to overwrite a previously bound value, silently corrupting query results. Replace rand() with bin2hex(random_bytes(4)) which uses the OS CSPRNG, produces 8 hex characters of uniform output, and has a collision probability of 1 in 4 billion per query — negligible even under high concurrency.
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Problem
CaseSensitiveCompareValueTraitusesrand()to generate unique named placeholder suffixes when binding values for case-sensitive MySQL/MariaDB comparisons:rand()is a non-cryptographic PRNG. Under concurrent load, or on platforms where the PHP PRNG has low entropy, duplicate values are possible. A collision causes CakePHP's query binder to silently overwrite a previously bound value, producing incorrect query results without raising an error.Fix
Replace
rand()withbin2hex(random_bytes(4))which reads from the OS CSPRNG:This produces 8 hex characters (32 bits of uniform entropy), giving a collision probability of ~1 in 4 billion per invocation — negligible even under high concurrency.
Applied to both
getCaseSensitiveValue()andgetCaseSensitiveValues().Impact
random_bytes()is available in all PHP versions ≥ 7.0