#VU16317 Heap-based buffer overflow in PHP

Vulnerability identifier: #VU16317

Vulnerability risk: Low

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: N/A

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
PHP
Universal components / Libraries / Scripting languages

Vendor: PHP Group

Description
The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists due to heap-based buffer overflow while fuzzing with AFL using an ASAN instrumented PHP. A remote attacker can disable the ZEND allocator, use ASAN (or valgrind/etc?) with a crafted phar as input, trigger memory corruption and cause the service to crash.

Mitigation
The vulnerability has been addressed in the versions 5.6.39, 7.0.33, 7.1.25, 7.2.13, 7.3.0.

Vulnerable software versions

PHP: 5.6.0 - 5.6.38, 7.0.0 - 7.0.32, 7.1.0 - 7.1.24, 7.2.0 - 7.2.12

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External links
https://bugs.php.net/bug.php?id=77143

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.