CRITICAL

CVE-2026-49819

UpSnap - Unauthenticated Initial-Superuser Takeover Chains to Root RCE via wake_cmd

CVSS v3

9.8

CRITICAL

EPSS Score

exploit probability

CISA KEV

No

known exploited

Exploitation

SSVC status

Description

UpSnap is a wake on lan web app. Versions 4.4.1 through 5.3.5 are vulnerable to a missing-authentication / privilege-escalation chain in `pb.HandlerInitSuperuser` (`backend/pb/handlers.go:249`), reachable as `POST /api/upsnap/init-superuser`. The vulnerable code lacks any authentication, setup token, IP allow-list, or rate limit and is gated only by a `totalSuperusers > 0` count check — a condition that is false on every fresh install — allowing an unauthenticated network-adjacent attacker to re

Technical details

CVSS v3 Vector
3.1
Published
8/13/2026
Last Modified
8/13/2026

Frequently asked questions

What is CVE-2026-49819?

UpSnap is a wake on lan web app. Versions 4.4.1 through 5.3.5 are vulnerable to a missing-authentication / privilege-escalation chain in `pb.HandlerInitSuperuser` (`backend/pb/handlers.go:249`), reachable as `POST /api/upsnap/init-superuser`. The vulnerable code lacks any authentication, setup token, IP allow-list, or rate limit and is gated only by a `totalSuperusers > 0` count check — a condition that is false on every fresh install — allowing an unauthenticated network-adjacent attacker to re

Is CVE-2026-49819 actively exploited?

Active exploitation of CVE-2026-49819 has not been confirmed. The EPSS score is N/A%, indicating the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-49819?

CVE-2026-49819 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string 3.1.

Is CVE-2026-49819 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.