Heap-based buffer underflow in php (Alpine package)

1) Heap-based buffer underflow

EUVDB-ID: #VU4197

Risk: Critical

CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]

CVE-ID: CVE-2012-2688

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: No

Description

The vulnerability allows a remote attacker to cause DoS conditions or execute arbitrary code on the target system.

The weakness exists due to heap-based buffer underflow in the PHP scandir() function. A remote attacker can create specially crafted files, upload them to a directory the scandir() function runs on and cause the PHP interpreter to crash or execute arbitrary code with privileges of the web server.

Successful exploitation of the vulnerability results in denial of service or arbitrary code execution on the vulnerable system.

Note: the vulnerability was being actively exploited.

Mitigation

Install update from vendor's website.

Vulnerable software versions

php (Alpine package): 5.3.3-r0 - 5.3.12-r0

CPE2.3

• cpe:2.3:o:alpine:php_alpine_package:5.3.3-r0:*:*:*:*:alpine_linux:*:1.10
• cpe:2.3:o:alpine:php_alpine_package:5.3.3-r2:*:*:*:*:alpine_linux:*:1.10
• cpe:2.3:o:alpine:php_alpine_package:5.3.3-r3:*:*:*:*:alpine_linux:*:1.10

External links

https://git.alpinelinux.org/aports/commit/?id=08fffe9a968660587cea5659d1d7e1c0cad15b6e
https://git.alpinelinux.org/aports/commit/?id=13fc90f3d7b3457447df4caa12628505bea6fc9e
https://git.alpinelinux.org/aports/commit/?id=d0fc255e5c7fd2c969eb7dd64e76bed93e761745
https://git.alpinelinux.org/aports/commit/?id=b9d1b15acff7eb38e5adec24faeaabf92cf93390

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, a fully functional exploit for this vulnerability is available.