JVN#65294474
Multiple vulnerabilities in TTSSH2 plugin of Tera Term

Overview

TTSSH2 plugin of Tera Term provided by TeraTerm Project contains multiple vulnerabilities.

Products Affected

• TTSSH2 1.00 alpha1 to 3.6.1

Description

TTSSH2 plugin of Tera Term provided by TeraTerm Project contains the following vulnerabilities:

• Unsigned to Signed Conversion Error (CWE-196)
  • CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N Base Score 5.1
  • CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L Base Score 6.3
  • CVE-2026-58317
• Improper Handling of Length Parameter Inconsistency (CWE-130)
  • CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N Base Score 5.1
  • CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L Base Score 6.3
  • CVE-2026-60060

Impact

The following conditions may occur when Tera Term attempts to establish an SSH connection to a server set up by an attacker:

• An out-of-bounds read may result in data from adjacent memory being treated as part of an incoming packet.
• An out-of-bounds write may occur. The attacker cannot freely control the value written; only a temporary null-byte ('\0') write followed by restoration of the original value is possible.

Solution

Update the Software
Update the software to the latest version in the Tera Term 5 series according to the information provided by the developer.
The developer has released the following version to address these vulnerabilities:

• TTSSH2 3.6.2 (Tera Term 5.6.2)