CVE-2026-58317

Unsigned to Signed Conversion Error (CWE-196) vulnerability exists in TTSSH2 plugin of Tera Term provided by TeraTerm Project. When Tera Term attempts to establish an SSH connection to a server set up by an attacker, out-of-bounds read/write may occur. As a result, the contents of adjacent memory regions may be transmitted to the server, and Tera Term may behave unexpected or terminate abnormally.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector : AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

Exploitability : 2.8 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://jvn.jp/en/jp/JVN65294474/
https://teratermproject.github.io/SA/JVN65294474-en.html
https://teratermproject.github.io/SA/JVN65294474.html

Configurations

No configuration.

History

24 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Existe una vulnerabilidad de error de conversión de sin signo a con signo (CWE-196) en el plugin TTSSH2 de Tera Term proporcionado por TeraTerm Project. Cuando Tera Term intenta establecer una conexión SSH con un servidor configurado por un atacante, puede ocurrir una lectura/escritura fuera de límites. Como resultado, el contenido de las regiones de memoria adyacentes puede ser transmitido al servidor, y Tera Term puede comportarse de forma inesperada o terminar de forma anómala.

Information

Published : 2026-07-17 05:16

Updated : 2026-10-24 20:10

NVD link : CVE-2026-58317

Mitre link : CVE-2026-58317

CVE.ORG link : CVE-2026-58317

JSON object : View

Products Affected

No product.

CWE

CWE-196

Unsigned to Signed Conversion Error

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