Path traversal in Loki

1) Path traversal

EUVDB-ID: #VU64412

Risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-36156

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 header value X-Scope-OrgID is used to construct file paths for rules files. A remote attacker can send a specially crafted HTTP request and read arbitrary files on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Loki: 0.1.0 - 2.2.0

External links

http://github.com/grafana/loki/pull/4020#issue-694377133
http://github.com/grafana/loki/releases/tag/v2.3.0

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.