#VU39753 Improper Neutralization of Special Elements in Output Used by a Downstream Component in PEAR - CVE-2017-5630

Vulnerability identifier: #VU39753

Vulnerability risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2017-5630

CWE-ID: CWE-74

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
PEAR
Universal components / Libraries / Scripting languages

Vendor: PHP Group

Description

The vulnerability allows a remote non-authenticated attacker to manipulate data.

PECL in the download utility class in the Installer in PEAR Base System v1.10.1 does not validate file types and filenames after a redirect, which allows remote HTTP servers to overwrite files via crafted responses, as demonstrated by a .htaccess overwrite.

Mitigation
Install update from vendor's website.

Vulnerable software versions

PEAR: 1.10.1

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External links
https://pear.php.net/bugs/bug.php?id=21171
https://www.securityfocus.com/bid/95882
https://www.exploit-db.com/exploits/41185/

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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.