Juniper Networks has released patches for multiple vulnerabilities in the J-Web component of Junos OS on SRX series firewalls and EX series switches, including a high-severity bug.
Accessible from a browser, the J-Web interface allows administrators to monitor, configure, troubleshoot, and manage devices running the Junos operating system.
The most severe of the resolved issues is a cross-site scripting flaw tracked as CVE-2024-21620 (CVSS score of 8.8), which could allow an attacker to craft a malicious URL that, when visited by a user, could lead to the execution of arbitrary commands with the permissions of the user, including those of an administrator.
Juniper Networks says the flaw has been patched in Junos OS versions 20.4R3-S10, 21.2R3-S8, 21.4R3-S6, 22.1R3-S5, 22.2R3-S3, 22.3R3-S2, 22.4R3-S1, 23.2R2, 23.4R2, and subsequent releases.
Another security defect resolved in the J-Web interface, CVE-2024-21619, could allow an unauthenticated attacker to access sensitive information over the network.
“When a user logs in, a temporary file which contains the configuration of the device (as visible to that user) is created in the /cache folder. An unauthenticated attacker can then attempt to access such a file by sending a specific request to the device trying to guess the name of such a file. Successful exploitation will reveal configuration information,” Juniper Networks notes in an advisory.
Junos OS versions 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S6, 22.1R3-S5, 22.2R3-S3, 22.3R3-S2, 22.4R3, 23.2R1-S2, 23.2R2, 23.4R1, and subsequent releases address this bug.
The networking technology company also resolved two missing authentication bugs that could allow an unauthenticated attacker to send crafted requests over the network and upload arbitrary files via J-Web (CVE-2023-36846), or download and upload arbitrary files (CVE-2023-36851).
Successful exploitation of these security holes could impact file system integrity. CVE-2023-36851 may also be chained with other vulnerabilities, Juniper says.
As a workaround for all four vulnerabilities, Juniper recommends disabling J-Web or limiting access to trusted hosts only.
The company makes no mention of any of these flaws being exploited in attacks.
The US cybersecurity agency CISA advises organizations to review Juniper’s advisory and apply the available patches as soon as possible, warning that attackers could exploit these bugs to take control of an affected system.
WatchTowr researcher Aliz Hammond, who identified CVE-2024-21619 and CVE-2024-21620, reports that Juniper Networks published its out-of-cycle bulletin documenting the bugs after being called out for not mentioning them when releasing patches earlier this month.
The technology company told the researcher that its assessment of the vulnerabilities had changed, and that it has reviewed its process of applying for CVE identifiers, which typically involves applying for CVEs late in the reporting cycle. The company said it planned to apply for CVEs once patches were released for all supported releases.
Updated with additional information from WatchTowr.