CVE-2026-23759
Perle IOLAN STS/SCS terminal server models with firmware versions prior to 6.0 allow authenticated OS command injection via the restricted shell accessed over Telnet or SSH.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.57%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Perle IOLAN STS/SCS terminal server models with firmware versions prior to 6.0 allow authenticated OS command injection via the restricted shell accessed over Telnet or SSH. The shell 'ps' command does not perform proper argument sanitization and passes user-supplied parameters into an 'sh -c' invocation running as root. An authenticated attacker who can log in to the device can inject shell metacharacters after the 'ps' subcommand to execute arbitrary OS commands with root privileges, leading to full compromise of the underlying operating system.
- CVSS 4.0
- 8.6 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/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/M
- EPSS
- 1.57% probability · 75th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-78
- Source
- disclosure@vulncheck.com
EPSS 1.6% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.