CVE-2026-49819Public exploitNetwork attack vectorHinoki check available

Unauthenticated root command execution via superuser takeover

Published Aug 12, 2026 · Updated Aug 12, 2026

Missing authentication in UpSnap 4.4.1 through 5.3.5 allows remote attackers to claim the initial superuser account. HandlerInitSuperuser checks only whether a superuser exists before saving attacker-supplied credentials and returning a 14-day JWT. When no superuser exists, that JWT permits creation of a device whose wake_cmd the server passes to the platform shell, executing commands with the UpSnap process's privileges.

CVSS severity9.8
Critical
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Missing authentication in UpSnap 4.4.1 through 5.3.5 allows remote attackers to claim the initial superuser account. HandlerInitSuperuser checks only whether a superuser exists before saving attacker-supplied credentials and returning a 14-day JWT. When no superuser exists, that JWT permits creation of a device whose wake_cmd the server passes to the platform shell, executing commands with the UpSnap process's privileges.

The record

CVE
CVE-2026-49819
Published
Aug 12, 2026
Updated
Aug 12, 2026
Vendor
seriousm4x
Product
UpSnap
Classifications
CWE-862, CWE-78, CWE-269, CWE-306, T1059, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=>= 4.4.1, < 5.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

seriousm4x · UpSnapversion=>= 4.4.1, < 5.4.0

Published CVSS scores

9.8GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE-269Improper Privilege Management
CWE-306Missing Authentication for Critical Function
T1059Command and Scripting Interpreter
T1190Exploit Public-Facing Application

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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