CVE-2026-36540
📛 CVE Title
CVE-2026-36540
Description
Netis AC1200 Router NC21 V4.0.1.4296 is vulnerable to unauthenticated command injection via the /cgi-bin/skk_set.cgi endpoint. The password and new_pwd_confirm POST parameters are passed directly to the underlying OS shell without sanitization. An attacker can inject arbitrary shell commands by wrapping them in backticks (`) and encoding them in base64. Because the endpoint requires no authentication, any device on the LAN can achieve full Remote Code Execution on the router's operating system with a single HTTP POST request.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- mitre
- CVSS severity
- high
- CVSS score
- 7.3 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L- Effective score
- 7.3 / 10 HIGH source: CNA overview
- CWE(s)
- —
- Reserved
- 2026-04-06
- Published
- 2026-05-27 00:00 UTC
- Last updated
- 2026-05-28 13:42 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/36xxx/CVE-2026-36540.json
- Linked Threat
- CVE-2026-36540 — CVE-2026-36540
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-27 14:16:45 UTC
- NVD last modified
- 2026-07-05 02:17:48 UTC
- NVD CVSS v3.1
- 7.3 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.4 / 10
- EPSS score
- 0.0132 (probability of exploitation in next 30 days)
- EPSS percentile
- 67.87% vs all CVEs — higher = more likely to be exploited, as of 2026-07-26
NVD-assigned CWE(s):
CWE-77
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-07-27 12:02 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-32687 - Assigner
- mitre
- Published
- May 27, 2026, 12:00:00 AM
- Updated
- Jul 5, 2026, 1:35:00 AM
- EUVD base score (CVSS 3.1)
-
7.3 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - EUVD-reported EPSS
- 1.3200
- Vendors
- n/a
- Products
-
n/a (n/a)
- Aliases
-
GHSA-x2w7-3ffq-rg3v
ENISA description: Netis AC1200 Router NC21 V4.0.1.4296 is vulnerable to unauthenticated command injection via the /cgi-bin/skk_set.cgi endpoint. The password and new_pwd_confirm POST parameters are passed directly to the underlying OS shell without sanitization. An attacker can inject arbitrary shell commands by wrapping them in backticks (`) and encoding them in base64. Because the endpoint requires no authentication, any device on the LAN can achieve full Remote Code Execution on the router's operating system with a single HTTP POST request.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| n/a | n/a |
n/a (affected)
|
— |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
Web references (5)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- http://netis-system.com tenable:netis-system.com
- https://github.com/sir3ns/cve-disclosure/blob/main/CVE-2026-36540/readme.md tenable:github.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-36540 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-36540 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/sir3ns/cve-disclosure/blob/main/CVE-2026-36540/readme.md cve@mitre.org
- https://github.com/sir3ns/cve-disclosure/blob/main/CVE-2026-36540/readme.md 134c704f-9b21-4f2e-91b3-4a467353bcc0
Remediations (19)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.qualys.com
May 2026's Patch Tuesday arrives with Microsoft addressing a fresh set of vulnerabilities across its ecosystem, reinforcing the ongoing need for timely patching in an increasingly threat-heavy…
2026-06-04 00:19 UTC -
web:blog.talosintelligence.com
Microsoft has released its monthly security update for May 2026 , which includes 137 vulnerabilities affecting a range of products, including 16 that Microsoft marked as "critical".
2026-06-04 00:19 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-06-04 00:19 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-06-04 00:19 UTC -
web:thecyberexpress.com
Microsoft has rolled out its May 2026 Patch Tuesday security updates, delivering fixes for approximately 120 vulnerabilities across Windows, Microsoft Office, networking services, and enterprise platforms.
2026-06-04 00:19 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-06-04 00:19 UTC -
web:www.helpnetsecurity.com
Microsoft has marked May 2026 Patch Tuesday by releasing fixes for 120+ CVE -numbered vulnerabilities, none of which are actively exploited.
2026-06-04 00:19 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-06-04 00:19 UTC -
web:www.pdq.com
May 2026 Patch Tuesday is here, and PDQ is back with another recap. Will we see another month of increased CVE volume? Is AI to blame? Dive in to learn more.
2026-06-04 00:19 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's June 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-06-04 00:19 UTC -
web:cvefeed.io
Solution Patch Netis AC1200 Router or apply vendor-supplied security updates to fix command injection vulnerability. Update the router firmware to the latest version. Apply any available security patches from the vendor. Restrict access to the router's management interface.
2026-06-19 02:27 UTC -
web:github.com
Because the endpoint requires no authentication, any device on the LAN can achieve full Remote Code Execution on the router's operating system with a single HTTP POST request. The vendor (Netis Systems) was contacted but did not respond. No patch has been released as of the publication date.
2026-06-19 02:27 UTC -
web:krebsonsecurity.com
For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?
2026-06-19 02:27 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.
2026-06-19 02:27 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-06-19 02:27 UTC -
web:www.csoonline.com
Days after Microsoft patched a high-severity issue affecting its Windows Defender antivirus tool through April's Patch Tuesday, researchers warn of another vulnerability that could enable SYSTEM ...
2026-06-19 02:27 UTC -
web:www.microsoft.com
A note on this month's Patch Tuesday Tuesday, May 12, 2026 Each Patch Tuesday looks a little different. Some months are quieter, others are larger. This month's release sits on the larger side of a hotpatch month, and we expect releases to continue trending larger for some time. Every update reflects Read More MSRC Patch Tuesday Security
2026-06-19 02:27 UTC -
web:www.tenable.com
Netis AC1200 Router NC21 V4.0.1.4296 is vulnerable to unauthenticated command injection via the /cgi-bin/skk_set.cgi endpoint. The password and new_pwd_confirm POST parameters are passed directly to the underlying OS shell without sanitization. An attacker can inject arbitrary shell commands by wrapping them in backticks (`) and encoding them in base64. Because the endpoint requires no ...
2026-06-19 02:27 UTC -
web:www.thehackerwire.com
How do I fix or mitigate CVE-2026-36540 ? To protect against CVE-2026-36540 , you should: (1) Apply the latest security patches from the vendor, (2) Check official security advisories for specific remediation steps, (3) Update affected software to the latest version, and (4) Monitor your systems for any signs of exploitation.
2026-06-19 02:27 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-36540.json.
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