In PHP versions:8.1.* before 8.1.34, 8.2.* before 8.2.30, 8.3.* before 8.3.29, 8.4.* before 8.4.16, 8.5.* before 8.5.1, a heap buffer overflow occurs in array_merge() when the total element count of packed arrays exceeds 32-bit limits or HT_MAX_SIZE, due to an integer overflow in the precomputation of element counts using zend_hash_num_elements(). This may lead to memory corruption or crashes and affect the integrity and availability of the target server.
2025-12-27T20:15:40.570
2026-01-24T11:15:49.520
Modified
CVSSv3.1: 6.5 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | php | php | < 8.1.34 | Yes |
| Application | php | php | < 8.2.30 | Yes |
| Application | php | php | < 8.3.29 | Yes |
| Application | php | php | < 8.4.16 | Yes |
| Application | php | php | < 8.5.1 | Yes |