CVE-2026-49864Public exploitNetwork attack vectorHinoki check available

SSH command injection via unescaped download filename

Published Aug 13, 2026 · Updated Aug 13, 2026

DOM XSS in butlerx WeTTY before 3.0.4 allows remote attackers to execute commands in a victim's SSH session via terminal output. The file-download handler base64-decodes an attacker-controlled filename and inserts it twice into Toastify HTML with markup escaping disabled. The victim must keep an active session open and render the crafted escape sequence; default settings then permit script execution, terminal-data reading, and keystroke injection.

CVSS severity8.6
High
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

DOM XSS in butlerx WeTTY before 3.0.4 allows remote attackers to execute commands in a victim's SSH session via terminal output. The file-download handler base64-decodes an attacker-controlled filename and inserts it twice into Toastify HTML with markup escaping disabled. The victim must keep an active session open and render the crafted escape sequence; default settings then permit script execution, terminal-data reading, and keystroke injection.

The record

CVE
CVE-2026-49864
Published
Aug 13, 2026
Updated
Aug 13, 2026
Vendor
butlerx
Product
WeTTY
Classifications
CWE-79, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.0.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

butlerx · WeTTYversion=< 3.0.4

Published CVSS scores

8.6GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059Command and Scripting Interpreter

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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