backmeup (npm): OS Command Injection via Backup Option Values
Summary
| CVE | CVE-2026-71243 |
|---|---|
| State | PUBLISHED |
| Assigner | TuranSec |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-05 11:16:27 UTC |
| Updated | 2026-08-05 13:24:48 UTC |
| Description | The backmeup npm package assembles shell command strings by directly concatenating its option values (name, source, destination, filter) - e.g. cmd = "mkdir -p " + path.join(info.destination, info.name) + "; " - and executes the resulting string through a shell via ssh2-exec (locally via child_process, or remotely via SSH when an ssh handle is supplied), rather than using execFile/spawn with an argument array. The only processing applied is path.normalize()/path.join(), which do not neutralize shell metacharacters (;, |, &, $(), backticks, newline). Any application that passes attacker-influenced values into these options (e.g. a user-chosen backup name) is vulnerable to arbitrary OS command execution on the backup host, or on the remote SSH target when one is configured. |
Risk And Classification
Primary CVSS: v3.1 8.8 HIGH from 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.004160000 probability, percentile 0.343240000 (date 2026-08-07)
Problem Types: CWE-78 | CWE-78 CWE-78 OS Command Injection
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c | Secondary | 8.8 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 8.8 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/adaltas/node-backmeup | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Timur Juraev (en)
There are currently no legacy QID mappings associated with this CVE.