FR
live
High CVSS 8.6

CVE-2026-49864

NVD analysis in progress

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.

What this means

Exposure
Exploitable remotely over the network and without authentication — but only if a user opens booby-trapped content.
Impact
An attacker can read sensitive data, modify or destroy data and degrade the service.
Weakness
Attacker-supplied script runs in other users’ browsers (cross-site scripting).
Likelihood
Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.

What to doFold into the next patch cycle.

Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.

Published
13 August 2026
CVSS
8.6 (v4.0) CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/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
EPSS
0.33% probability of exploitation within 30 days · above 26% of all CVEs
Weakness
CWE-79
Sources
nvd
References

Type at least two characters.

navigate open esc dismiss