Heap-out-of-bounds write in php7 (Alpine package)

Published: 2017-07-07

Risk	High
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2017-9226
CWE-ID	CWE-787
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	php7 (Alpine package) Operating systems & Components / Operating system package or component
Vendor	Alpine Linux Development Team

Security Bulletin

This security bulletin contains one high risk vulnerability.

1) Heap-out-of-bounds write

EUVDB-ID: #VU7346

Risk: High

CVSSv3.1: 8.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-9226

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

The vulnerability allows a remote attacker to execute arbitrary code.

The weakness exists in the mbstring due to heap out-of-bounds write or read occurs in next_state_val() during regular expression compilation. A remote attacker can supply a malformed regular expression containing an octal number in the form of '\700', trigger
out-of-bounds write memory corruption and execute arbitrary code with web server privileges.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation

Install update from vendor's website.

Vulnerable software versions

php7 (Alpine package): 7.0.7-r0 - 7.0.25-r0

External links

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.