Heap buffer overflow in array_merge()

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.

Problem type

Affected products

PHP Group

PHP

< 8.1.34 - AFFECTED

< 8.2.30 - AFFECTED

< 8.3.29 - AFFECTED

< 8.4.16 - AFFECTED

< 8.5.1 - AFFECTED

References

github.com

https://github.com/php/php-src/security/advisories/GHSA-h96m-rvf9-jgm2

JSON source

https://cveawg.mitre.org/api/cve/CVE-2025-14178

Click to expand

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    "assignerOrgId": "dd77f84a-d19a-4638-8c3d-a322d820ed2b",
    "assignerShortName": "php",
    "dateUpdated": "2025-12-27T19:27:41.691Z",
    "dateReserved": "2025-12-06T06:25:31.535Z",
    "datePublished": "2025-12-27T19:27:41.691Z",
    "state": "PUBLISHED"
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  "containers": {
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        "dateUpdated": "2025-12-27T19:27:41.691Z"
      },
      "datePublic": "2025-12-18T00:00:00.000Z",
      "title": "Heap buffer overflow in array_merge()",
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          "lang": "en",
          "value": "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.",
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