#VU16315 NULL pointer dereference in PHP - CVE-2018-19935

Vulnerability identifier: #VU16315

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: CVE-2018-19935

CWE-ID: CWE-476

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 NULL pointer dereference in _php_imap_mail when improper check of wheater message. A remote attacker can supply specially crafted message, trigger NULL pointer dereference and cause the service to crash.

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

Vulnerable software versions

PHP: 5.6.0 - 5.6.38, 7.0.0 - 7.0.32

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External links
https://bugs.php.net/bug.php?id=77020

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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.