SB2021080529 - Multiple vulnerabilities in Pulse Connect Secure

Description

This security bulletin contains information about 6 secuirty vulnerabilities.

1) Arbitrary file upload (CVE-ID: CVE-2021-22937)

The vulnerability allows a remote user to compromise vulnerable system.

The vulnerability exists due to insufficient validation of file during file upload within the administrative interface. A remote privileged user can upload a malicious archive and execute it on the server.

Note, the vulnerability is being actively exploited in the wild as of August 2021.

2) Path traversal (CVE-ID: CVE-2021-22933)

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

The vulnerability exists due to input validation error when processing directory traversal sequences. A remote privileges user can send a specially crafted HTTP request and delete arbitrary files on the system.

3) Buffer overflow (CVE-ID: CVE-2021-22934)

The vulnerability allows a remote user to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in a load-balanced configuration. A remote privileges user can create a specially crafted HTTP request to the system, trigger memory corruption and execute arbitrary code on the target system.

4) OS Command Injection (CVE-ID: CVE-2021-22935)

The vulnerability allows a remote user to execute arbitrary shell commands on the target system.

The vulnerability exists due to improper input validation. A remote privileges user can send a specially crafted HTTP request to the system and execute arbitrary OS commands.

5) Cross-site scripting (CVE-ID: CVE-2021-22936)

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 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.

6) OS Command Injection (CVE-ID: CVE-2021-22938)

The vulnerability allows a remote user to execute arbitrary shell commands on the target system.

The vulnerability exists due to improper input validation. A remote administrator can send a specially crafted HTTP request to the system and execute arbitrary OS commands.

Remediation

Install update from vendor's website.

References

• https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44858/p?pubstatus=o
• https://us-cert.cisa.gov/ncas/current-activity/2021/08/24/cisa-releases-five-pulse-secure-related-mars