Rewterz Threat Advisory – Juniper Networks Junos OS Multiple Vulnerabilities

Severity

Medium

Analysis Summary

CVE-2021-0272

Juniper Networks Junos OS is vulnerable to a denial of service, caused by a kernel memory leak flaw. An attacker can exploit this vulnerability to cause denial-of-service conditions by sending specially crafted packets on the system.

CVE-2021-0271

Juniper Networks Junos OS is vulnerable to a denial of service, caused by a double-free flaw in the software forwarding interface daemon (sfid) process. A remote attacker can exploit this vulnerability to cause the sfid process to crash, resulting in a denial-of-service condition which is done by sending specially crafted ARP packets on the system.

CVE-2021-0269

Juniper Networks Junos OS could allow a remote attacker to bypass security restrictions, caused by improper handling of client-side parameters in the J-Web component. An attacker can exploit this vulnerability to input validation mechanisms, modify J-Web’s normal behavior, and bypass web application firewall rules.

CVE-2021-0268

Juniper Networks Junos OS is vulnerable to HTTP response splitting attacks. By injecting arbitrary HTTP headers, a remote attacker can exploit the vulnerability and cause the server to return a split response, once the URL is clicked. This would allow the attacker to perform further attacks, such as cross-site scripting, Web cache poisoning, and possibly obtain sensitive information.

CVE-2021-0267

Juniper Networks Junos OS is vulnerable to a denial of service, caused by improper input validation in the active-lease query portion in JDHCPD’ss DHCP Relay Agent. A remote attacker can exploit the vulnerability by sending a specially-crafted DHCP packet to cause the jdhcpd DHCP service to crash and results in a denial of service condition.

Impact

• Denial-of-Service
• Bypass Security
• HTTP response splitting

Affected Vendors

Juniper

Affected Products

• Juniper Networks Junos OS 17.3
• Juniper Networks Junos OS 16.1
• Juniper Networks Junos OS 18.1
• Juniper Networks Junos OS 18.2
• Juniper Networks Junos OS 18.4
• Juniper Networks Junos OS 12.3
• Juniper Networks EX2200-C Series
• Juniper Networks EX3200 Series
• Juniper Networks Junos OS 20.1

Remediation

Refer to the Juniper Networks Security website for more information about the affected products and mitigation techniques. https://kb.juniper.net/InfoCenter/index?page=content&id=JSA11160&cat=SIRT_1&actp=LIST