CVE-2026-49819

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Source

https://cve.org/CVERecord?id=CVE-2026-49819

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49819.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-49819

Aliases

GHSA-w4jr-728f-5jhq

Published

2026-08-12T23:13:46Z

Modified

2026-10-28T02:30:27Z

Severity

9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator

Summary

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

Details

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 register the initial superuser account, receive a long-lived JWT, and pivot to root remote code execution at backend/networking/wake.go:43 (exec.CommandContext(ctx, "/bin/sh", "-c", wake_cmd)). Version 5.4.0 fixes the issue.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-269",
        "CWE-306",
        "CWE-78",
        "CWE-862"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49819.json"
}

References

Affected packages

Git / github.com/seriousm4x/upsnap

Affected ranges

Type

GIT

Repo

https://github.com/seriousm4x/upsnap

Events

Introduced

47b81553befa785b73ddc8aff2c6774975791ff2

Fixed

92f9e295d5f761d874a6701245b2e38dc42cb85a

Database specific

Show details

{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "4.4.1"
                },
                {
                    "fixed": "5.4.0"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "original_tag": "5.4.0",
            "range": [
                {
                    "fixed": "92f9e295d5f761d874a6701245b2e38dc42cb85a"
                }
            ],
            "source": "REFERENCES_TAG"
        }
    ]
}

Affected versions

4.*

4.4.1

4.4.2

4.4.2-beta.1

4.4.2-beta.2

4.5.0

4.5.1

4.6.0

5.*

5.0.0

5.0.0-beta.1

5.0.0-beta.2

5.0.0-beta.3

5.0.1

5.0.1-beta.1

5.0.1-beta.2

5.0.2

5.0.3

5.0.4

5.0.5

5.0.5-beta.1

5.0.6

5.0.7

5.0.8

5.1.0

5.1.1

5.1.10-beta.1

5.1.2

5.1.3

5.1.4

5.1.5

5.1.6

5.1.7

5.1.8

5.1.9

5.2.0

5.2.0-beta.0

5.2.0-beta.1

5.2.1

5.2.2

5.2.3

5.2.4

5.2.5

5.2.6

5.2.7

5.2.8

5.3.0

5.3.0-beta.0

5.3.1

5.3.2

5.3.2-beta.0

5.3.3

5.3.4

5.3.5

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49819.json"