CVE-2026-58317
Tera Term TTSSH2 Plugin Unsigned to Signed Conversion Error
Description
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.
INFO
Published Date :
July 17, 2026, 5:16 a.m.
Last Modified :
July 17, 2026, 5:16 a.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-58317
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.0 | MEDIUM | ede6fdc4-6654-4307-a26d-3331c018e2ce | ||||
| CVSS 3.0 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | ede6fdc4-6654-4307-a26d-3331c018e2ce | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update Tera Term to the latest version.
- Apply any available security patches for Tera Term.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-58317.
| URL | Resource |
|---|---|
| https://jvn.jp/en/jp/JVN65294474/ | |
| https://teratermproject.github.io/SA/JVN65294474-en.html | |
| https://teratermproject.github.io/SA/JVN65294474.html |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-58317 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-58317
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-58317 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-58317 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'TeraTerm Project', 'product': 'TTSSH2', 'versions': [{'status': 'affected', 'version': '1.00 alpha1', 'versionType': 'semver', 'lessThanOrEqual': '3.6.1'}], 'defaultStatus': 'unaffected'}] Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:L/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:X/R:X/V:X/RE:X/U:X Added CVSS V3 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L Added CWE CWE-196 Added Reference https://jvn.jp/en/jp/JVN65294474/ Added Reference https://teratermproject.github.io/SA/JVN65294474-en.html Added Reference https://teratermproject.github.io/SA/JVN65294474.html