Description
An Authentication Bypass by Primary Weakness in the FTP server of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to get limited read-write access to files on the device. When the FTP server is enabled and a user named "ftp" or "anonymous" is configured, that user can login without providing the configured password and then has read-write access to their home directory. This issue affects Junos OS: * all versions before 22.4R3-S8, * 23.2 versions before 23.2R2-S3, * 23.4 versions before 23.4R2.
Affected products
juniper: junos
References1
- supportportal.juniper.net/JSA103167 Vendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:M/U:X - EPSS — exploit probability
- 0% percentile: 22 · as of 9 November 2026
- CWE
- CWE-305
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.