Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). EPSS scores by FIRST (EPSS SIG), generated by Empirical Security. Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-6158 is a medium-severity Command Injection (CWE-77) vulnerability in Totolink N300RH (inferred from references). Its CVSS base score is 6.9 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 19% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
A flaw has been identified in the Totolink N300RH router running firmware version 6.1c.1353_B20190305. The issue resides in the setUpgradeUboot function within the upgrade.so component, where improper handling of the FileName argument permits operating system command injection. The vulnerability is tracked under CVE-2026-6158 and carries a CVSS v4 score of 6.9, with associated weaknesses classified as CWE-77 and CWE-78.
Remote, unauthenticated attackers can exploit the flaw over the network to execute arbitrary operating system commands. Successful exploitation grants limited effects on confidentiality, integrity, and availability of the affected device, and a publicly available proof-of-concept has already been released.
The EPSS probability currently stands at 0.0115 after reaching a peak of 0.0486, reflecting a clear upward trajectory that indicates growing exploitation interest following disclosure. Reference materials include a GitHub repository containing exploit code for the N300RH, multiple Vuldb entries, and the vendor website, though no explicit patch or mitigation guidance is detailed in the available records.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-21851
Vulnerability Data
A flaw has been found in Totolink N300RH 6.1c.1353_B20190305. Affected is the function setUpgradeUboot of the file upgrade.so. This manipulation of the argument FileName causes os command injection. The attack is possible to be carried out remotely. The exploit has…
more
been published and may be used.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
—
V1.2.5V1.2.8
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover command-construction flaws before deployment.
Input validation directly stops construction of commands from untrusted data containing special elements.
Least privilege reduces the permissions available to any process that could be subverted by injected commands.
Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.
Secure engineering principles include proper neutralization and safe command construction practices.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.
Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development catches command-injection vulnerabilities before release.
Secure coding standards require proper escaping and parameterization of commands, directly eliminating CWE-77.
Hardening callouts derived
DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.
- No fine-grained STIG row for CWE-77, a class-level weakness, and none of its children carries one either.