SB2023042507 - Multiple vulnerabilitiesin Zyxel firewalls
Published: April 25, 2023 Updated: June 14, 2024
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Stored cross-site scripting (CVE-ID: CVE-2023-27990)
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:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/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. A remote user can inject 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) OS Command Injection (CVE-ID: CVE-2023-27991)
CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.
The vulnerability exists due to improper input validation. A remote user can pass specially crafted data to the application and execute arbitrary OS commands on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
3) OS Command Injection (CVE-ID: CVE-2023-28771)
CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber
The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.
The vulnerability exists due to improper input validation. A remote unauthenticated attacker can pass specially crafted data to the application and execute arbitrary OS commands on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Remediation
Install update from vendor's website.
References
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-remote-command-injection-vulnerability-of-firewalls
- https://www.zyxel.com/global/en/support/security-advisories/zyxels-guidance-for-the-recent-attacks-on-the-zywall-devices