Directory traversal in lighttpd

1) Path traversal

EUVDB-ID: #VU15757

Risk: Low

CVSSv3.1: 3.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-19052

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences. A remote attacker can send a specially crafted HTTP request and read arbitrary file located in a directory above an alias target, with a specific mod_alias configuration where the matched alias lacks a trailing '/' character, but the alias target filesystem path does have a trailing '/' character

Mitigation

Install updates from vendor's website.

Vulnerable software versions

lighttpd: 1.4.1 - 1.4.49

External links

http://github.com/lighttpd/lighttpd1.4/commit/2105dae0f9d7a964375ce681e53cb165375f84c1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.