CVE-2025-49597: 
PHP vulnerability analysis and mitigation

CVE-2025-49597 affects handcraftedinthealps goodby-csv, a highly memory efficient, flexible and extendable open-source CSV import/export library. The vulnerability was discovered and disclosed on June 13, 2025, affecting versions 1.4.2 and prior (GitHub Advisory, NVD).

The vulnerability is related to insecure deserialization in the library's functionality. It presents as a gadget chain that could potentially be leveraged for remote code execution if the application deserializes untrusted data due to another vulnerability. The CVSS v3.1 base score is 3.9 (Low) with a vector string of CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L, indicating local access requirements, high attack complexity, and high privileges required (GitHub Advisory).

While the vulnerability itself presents no direct threat, it can be used as a vector to achieve remote code execution if an application deserializes untrusted data due to another vulnerability. The impact is considered Low with potential effects on confidentiality, integrity, and availability all rated as Low (GitHub Advisory).

The vulnerability has been patched in version 1.4.3 of goodby-csv. The fix involves adding a __wakeup() method to throw a BadMethodCallException when attempting to unserialize the CallbackCollection class. Users are advised to upgrade to version 1.4.3 or later (GitHub Advisory).