SB2021022315 - Multiple vulnerabilities in Pi-hole

Description

This security bulletin contains information about 2 vulnerabilities.

1) Cross-site scripting (CVE-ID: CVE-2020-35592)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:P/U:Clear

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data within the Options header in the admin/ URI. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

2) Session Fixation (CVE-ID: CVE-2020-35591)

CWE-ID: CWE-384 - Session Fixation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Green

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the failure to generate a new session cookie after the user is logged in. A remote attacker can trick a victim to visit a specially crafted website and gain access to another user's session.

Remediation

Install update from vendor's website.

References

• https://discourse.pi-hole.net/c/announcements/5
• https://n4nj0.github.io/advisories/pi-hole-multiple-vulnerabilities-i/