#VU22476 Out-of-bounds read in PHP - CVE-2019-9021

Vulnerability identifier: #VU22476

Vulnerability risk: Medium

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-9021

CWE-ID: CWE-125

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 gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition within the phar_detect_phar_fname_ext() function in ext/phar/phar.c (PHAR extension) when reading PHAR archives. A remote attacker can create a specially crafted PHAR archive, pass it to the affected application, trigger out-of-bounds read error and read contents of memory on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

PHP: 5.6.0 - 5.6.39, 7.1.0 - 7.1.25, 7.2.0 - 7.2.13, 7.3.0alpha1 - 7.3.0

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External links
https://bugs.php.net/bug.php?id=77247

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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.