Junos OS (SRX firewalls)
CVE-2024-21619: SRX Series and EX Series: J-Web - unauthenticated access to temporary files containing sensitive information
A Missing Authentication for Critical Function vulnerability combined with a Generation of Error Message Containing Sensitive Information vulnerability in J-Web of Juniper Networks Junos OS on SRX Series and EX Series allows an unauthenticated, network-based attacker to access sensitive system information.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Junos OS (SRX Series, EX Series) 0 | 20.4R3-S9 or later |
| Junos OS (SRX Series, EX Series) 21.2 | 21.2R3-S7 or later |
| Junos OS (SRX Series, EX Series) 21.3 | 21.3R3-S5 or later |
| Junos OS (SRX Series, EX Series) 21.4 | 21.4R3-S6 or later |
| Junos OS (SRX Series, EX Series) 22.1 | 22.1R3-S5 or later |
| Junos OS (SRX Series, EX Series) 22.2 | 22.2R3-S3 or later |
| Junos OS (SRX Series, EX Series) 22.3 | 22.3R3-S2 or later |
| Junos OS (SRX Series, EX Series) 22.4 | 22.4R3 or later |
| Junos OS (SRX Series, EX Series) 23.2 | 23.2R1-S2, 23.2R2 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A Missing Authentication for Critical Function vulnerability combined with a Generation of Error Message Containing Sensitive Information vulnerability in J-Web of Juniper Networks Junos OS on SRX Series and EX Series allows an unauthenticated, network-based attacker to access sensitive system information.
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.
This issue affects Juniper Networks Junos OS on SRX Series and EX Series: * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S7; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S6; * 22.1 versions earlier than 22.1R3-S5; * 22.2 versions earlier than 22.2R3-S3; * 22.3 versions earlier than 22.3R3-S2; * 22.4 versions earlier than 22.4R3; * 23.2 versions earlier than 23.2R1-S2, 23.2R2.
Workarounds
Disable J-Web, or limit access to only trusted hosts.
Exploitation
Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.