Out-of-bounds read in php7 (Alpine package)

1) Out-of-bounds read

EUVDB-ID: #VU25110

Risk: High

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-7060

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information or perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary condition when using certain "mbstring" functions to convert multibyte encodings. A remote attacker can supply data that will cause function "mbfl_filt_conv_big5_wchar" to read past the allocated buffer, trigger out-of-bounds read error and read contents of memory on the system or crash the application.

Mitigation

Install update from vendor's website.

Vulnerable software versions

php7 (Alpine package): 7.2.5-r0 - 7.2.26-r0

External links

http://git.alpinelinux.org/aports/commit/?id=37674ae79d4a86d8c65e91229951ff777ec29540
http://git.alpinelinux.org/aports/commit/?id=ec9d680b52bf5f756d39d57cd415ef638a1aac60
http://git.alpinelinux.org/aports/commit/?id=42c07d47c295b72e57f7dc851d590097aa6053ff
http://git.alpinelinux.org/aports/commit/?id=68838633d9df28ddca4f065d839b033d943bbb7b

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.