CVE-2026-49864

wetty provides terminal access in browser over http/https. Prior to version 3.0.4, the wetty client decodes a base64 filename from the file-download escape sequence and interpolates it raw into a Toastify HTML string (`escapeMarkup: false`). Any output the victim renders - a `cat`'d file, a tailed log, an SSH MOTD, a `curl` response - that contains `\x1b[5i...:...\x1b[4i` runs script in the wetty origin and types attacker-chosen keystrokes into the victim's SSH session. Version 3.0.4 fixes the issue.

CVSS

No CVSS.

References

Link	Resource
https://github.com/butlerx/wetty/security/advisories/GHSA-p26j-h7wj-r568
https://github.com/butlerx/wetty/security/advisories/GHSA-p26j-h7wj-r568

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 20:17

Updated : 2026-09-09 21:02

NVD link : CVE-2026-49864

Mitre link : CVE-2026-49864

CVE.ORG link : CVE-2026-49864

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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