CVE-2026-36540

HIGHPre-NVD 7.37.3—
EchelonGraph scoreMEDIUM confidence

Score 7.3 from GitHub Security Advisory (severity: HIGH) published 2026-05-27. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Elevated
7.3EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.3Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
7.3
EG Score
7.3(medium)
EG Risk
64(Attend)
EG Risk 64/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity73% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
1%
EPSS %ILE
68%
KEV
Not listed

Published

May 27, 2026

Last Modified

July 5, 2026

Advisory Details (2)

Auto-updated Jun 11, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

cve-disclosure/CVE-2026-36540/readme.md at main · sir3ns/cve-disclosure · GitHub

https://github.com/sir3ns/cve-disclosure/blob/main/CVE-2026-36540/readme.md
generic

netis-system.com - netis system Resources and Information.

http://netis-system.com

Vendor Advisories for CVE-2026-36540(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 11× in last 7d / 38× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 134 total refreshes for this CVE.

  1. 2026-07-27 14:13 UTCEPSS rescore
  2. 2026-07-26 14:54 UTCEPSS rescore
  3. 2026-07-26 14:54 UTCEPSS rescore
  4. 2026-07-25 14:18 UTCEPSS rescore
  5. 2026-07-25 14:18 UTCEPSS rescore
  6. 2026-07-24 14:17 UTCEPSS rescore
  7. 2026-07-24 14:17 UTCEPSS rescore
  8. 2026-07-23 14:18 UTCEPSS rescore
  9. 2026-07-23 14:18 UTCEPSS rescore
  10. 2026-07-23 03:10 UTCEG score recompute
  11. 2026-07-22 14:08 UTCEPSS rescore
  12. 2026-07-21 15:24 UTCEPSS rescore
  13. 2026-07-20 17:08 UTCEPSS rescore
  14. 2026-07-19 14:31 UTCEPSS rescore
  15. 2026-07-19 02:29 UTCEPSS rescore
  16. 2026-07-18 10:04 UTCEPSS rescore
  17. 2026-07-16 17:03 UTCEPSS rescore
  18. 2026-07-15 16:57 UTCEPSS rescore
  19. 2026-07-15 16:57 UTCEPSS rescore
  20. 2026-07-15 02:00 UTCEPSS rescore
  21. 2026-07-13 22:30 UTCEPSS rescore
  22. 2026-07-13 06:13 UTCEPSS rescore
  23. 2026-07-13 06:13 UTCEPSS rescore
  24. 2026-07-12 05:46 UTCEPSS rescore
  25. 2026-07-11 08:27 UTCEPSS rescore
Show 75 more
  1. 2026-07-09 19:10 UTCEPSS rescore
  2. 2026-07-08 15:15 UTCEPSS rescore
  3. 2026-07-07 13:46 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 16:27 UTCEPSS rescore
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-06 02:23 UTCEPSS rescore
  8. 2026-07-05 02:30 UTCEPSS rescore
  9. 2026-07-04 06:31 UTCEPSS rescore
  10. 2026-07-01 15:06 UTCEPSS rescore
  11. 2026-07-01 11:56 UTCGHSA enrichment
  12. 2026-06-30 23:22 UTCEPSS rescore
  13. 2026-06-29 14:46 UTCGHSA enrichment
  14. 2026-06-28 22:29 UTCGHSA enrichment
  15. 2026-06-28 14:07 UTCEPSS rescore
  16. 2026-06-28 07:30 UTCGHSA enrichment
  17. 2026-06-28 04:56 UTCEPSS rescore
  18. 2026-06-27 18:49 UTCGHSA enrichment
  19. 2026-06-27 06:58 UTCGHSA enrichment
  20. 2026-06-27 03:08 UTCEPSS rescore
  21. 2026-06-26 17:28 UTCGHSA enrichment
  22. 2026-06-25 21:24 UTCGHSA enrichment
  23. 2026-06-25 13:49 UTCEPSS rescore
  24. 2026-06-25 13:49 UTCEPSS rescore
  25. 2026-06-25 09:39 UTCGHSA enrichment
  26. 2026-06-24 14:05 UTCEPSS rescore
  27. 2026-06-23 21:33 UTCEPSS rescore
  28. 2026-06-23 21:33 UTCEPSS rescore
  29. 2026-06-21 14:56 UTCEPSS rescore
  30. 2026-06-21 14:56 UTCEPSS rescore
  31. 2026-06-21 01:59 UTCEPSS rescore
  32. 2026-06-19 19:25 UTCEPSS rescore
  33. 2026-06-19 19:25 UTCEPSS rescore
  34. 2026-06-18 17:52 UTCEPSS rescore
  35. 2026-06-18 17:52 UTCEPSS rescore
  36. 2026-06-17 21:30 UTCGHSA enrichment
  37. 2026-06-17 17:53 UTCEPSS rescore
  38. 2026-06-17 09:45 UTCGHSA enrichment
  39. 2026-06-16 21:54 UTCGHSA enrichment
  40. 2026-06-16 17:52 UTCEPSS rescore
  41. 2026-06-16 10:11 UTCGHSA enrichment
  42. 2026-06-15 22:27 UTCGHSA enrichment
  43. 2026-06-15 17:49 UTCEPSS rescore
  44. 2026-06-15 08:15 UTCGHSA enrichment
  45. 2026-06-14 23:18 UTCEPSS rescore
  46. 2026-06-14 20:29 UTCGHSA enrichment
  47. 2026-06-14 08:45 UTCGHSA enrichment
  48. 2026-06-13 23:00 UTCEPSS rescore
  49. 2026-06-13 21:02 UTCGHSA enrichment
  50. 2026-06-13 07:20 UTCGHSA enrichment
  51. 2026-06-12 23:12 UTCEPSS rescore
  52. 2026-06-12 23:12 UTCEPSS rescore
  53. 2026-06-12 19:33 UTCGHSA enrichment
  54. 2026-06-12 07:50 UTCGHSA enrichment
  55. 2026-06-11 20:06 UTCGHSA enrichment
  56. 2026-06-11 14:00 UTCEPSS rescore
  57. 2026-06-11 08:23 UTCGHSA enrichment
  58. 2026-06-10 22:18 UTCEPSS rescore
  59. 2026-06-10 20:39 UTCGHSA enrichment
  60. 2026-06-10 13:22 UTCEPSS rescore
  61. 2026-06-10 08:54 UTCGHSA enrichment
  62. 2026-06-09 21:11 UTCGHSA enrichment
  63. 2026-06-09 09:22 UTCGHSA enrichment
  64. 2026-06-08 21:38 UTCGHSA enrichment
  65. 2026-06-08 14:17 UTCEPSS rescore
  66. 2026-06-08 14:17 UTCEPSS rescore
  67. 2026-06-08 09:54 UTCGHSA enrichment
  68. 2026-06-07 22:10 UTCGHSA enrichment
  69. 2026-06-07 15:25 UTCEPSS rescore
  70. 2026-06-07 15:25 UTCEPSS rescore
  71. 2026-06-07 15:25 UTCEPSS rescore
  72. 2026-06-07 10:27 UTCGHSA enrichment
  73. 2026-06-06 22:44 UTCGHSA enrichment
  74. 2026-06-06 13:47 UTCEPSS rescore
  75. 2026-06-06 13:47 UTCEPSS rescore

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-36540?
CVE-2026-36540 is a high vulnerability published on May 27, 2026. Netis AC1200 Router NC21 V4.0.1.4296 is vulnerable to unauthenticated command injection via the /cgi-bin/skkset.cgi endpoint. The password and newpwd_confirm POST parameters are passed directly to the underlying OS shell without sanitization. An attacker can inject arbitrary shell commands by…
When was CVE-2026-36540 disclosed?
CVE-2026-36540 was first published in the National Vulnerability Database on May 27, 2026, with the most recent update on July 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-36540 actively exploited?
CVE-2026-36540 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 32.1% of all scored CVEs.
What is the CVSS score of CVE-2026-36540?
CVE-2026-36540 has a CVSS v3.1 base score of 7.3 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-36540?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-36540, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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