Vulnerability identifier: #VU7358

Vulnerability risk: Low

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: N/A

CWE-ID: CWE-284

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 obtain potentially sensitive information.

The weakness exists due to improper access control. A remote attacker can use negative offset parameter and a big string haystack to gain illegal memory access in zend_memnstr_ex function and read arbitrary files on the system.

Successful exploitation of the vulnerability results in information disclosure.

Mitigation
Update to version 7.0.21.

Vulnerable software versions

PHP: 7.0.0 - 7.0.20

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External links
http://php.net/ChangeLog-7.php#7.0.21
http://bugs.php.net/bug.php?id=73634

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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.