CVE-2020-13166

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: HIGH) published 2022-05-24. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Weaponized
9.8
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 78%
CISA-KEV: Not listedEPSS: 78%CVSS: 9.8Exploit: NoneExposed: 0

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

The management tool in MyLittleAdmin 3.8 allows remote attackers to execute arbitrary code because machineKey is hardcoded (the same for all customers' installations) in web.config, and can be used to send serialized ASP code.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
80(Track*)
EG Risk 80/100SSVC: Track*

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
Severity98% × 45%
Exploitation78% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS
99.5%
KEV
Not listed

Published

May 19, 2020

Last Modified

November 21, 2024

Advisory Details (1)

Auto-updated Jul 11, 2026
No patch confirmed yet.
generic

SSD Advisory - MyLittleAdmin PreAuth RCE - SSD Secure Disclosure

https://ssd-disclosure.com/ssd-advisory-mylittleadmin-preauth-rce/

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 15× in last 7d / 30× 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.

  1. 2026-07-23 14:15 UTCEPSS rescore
  2. 2026-07-23 14:15 UTCEPSS rescore
  3. 2026-07-23 01:49 UTCEG score recompute
  4. 2026-07-22 22:34 UTCEG score recompute
  5. 2026-07-22 14:05 UTCEPSS rescore
  6. 2026-07-21 15:22 UTCEPSS rescore
  7. 2026-07-21 15:22 UTCEPSS rescore
  8. 2026-07-20 17:04 UTCEPSS rescore
  9. 2026-07-19 14:28 UTCEPSS rescore
  10. 2026-07-19 14:28 UTCEPSS rescore
  11. 2026-07-19 02:26 UTCEPSS rescore
  12. 2026-07-19 02:26 UTCEPSS rescore
  13. 2026-07-18 10:02 UTCEPSS rescore
  14. 2026-07-16 16:59 UTCEPSS rescore
  15. 2026-07-16 16:59 UTCEPSS rescore
  16. 2026-07-15 16:55 UTCEPSS rescore
  17. 2026-07-13 22:27 UTCEPSS rescore
  18. 2026-07-12 05:44 UTCEPSS rescore
  19. 2026-07-11 08:24 UTCEPSS rescore
  20. 2026-07-07 13:43 UTCEPSS rescore
  21. 2026-07-04 06:28 UTCEPSS rescore
  22. 2026-06-30 23:20 UTCEPSS rescore
  23. 2026-06-30 23:20 UTCEPSS rescore
  24. 2026-06-27 03:06 UTCEPSS rescore
  25. 2026-06-25 13:47 UTCEPSS rescore
Show 37 more
  1. 2026-06-25 13:47 UTCEPSS rescore
  2. 2026-06-24 14:03 UTCEPSS rescore
  3. 2026-06-24 14:03 UTCEPSS rescore
  4. 2026-06-23 21:31 UTCEPSS rescore
  5. 2026-06-23 21:31 UTCEPSS rescore
  6. 2026-06-21 01:57 UTCEPSS rescore
  7. 2026-06-21 01:57 UTCEPSS rescore
  8. 2026-06-19 19:23 UTCEPSS rescore
  9. 2026-06-19 19:23 UTCEPSS rescore
  10. 2026-06-17 17:50 UTCEPSS rescore
  11. 2026-06-17 17:50 UTCEPSS rescore
  12. 2026-06-16 17:50 UTCEPSS rescore
  13. 2026-06-16 17:50 UTCEPSS rescore
  14. 2026-06-15 17:46 UTCEPSS rescore
  15. 2026-06-13 22:58 UTCEPSS rescore
  16. 2026-06-13 22:58 UTCEPSS rescore
  17. 2026-06-12 23:09 UTCEPSS rescore
  18. 2026-06-11 13:58 UTCEPSS rescore
  19. 2026-06-10 22:16 UTCEPSS rescore
  20. 2026-06-10 22:16 UTCEPSS rescore
  21. 2026-06-08 14:15 UTCEPSS rescore
  22. 2026-06-08 14:15 UTCEPSS rescore
  23. 2026-06-07 15:23 UTCEPSS rescore
  24. 2026-06-07 15:23 UTCEPSS rescore
  25. 2026-06-06 13:45 UTCEPSS rescore
  26. 2026-06-06 13:45 UTCEPSS rescore
  27. 2026-06-06 13:45 UTCEPSS rescore
  28. 2026-06-05 06:08 UTCEPSS rescore
  29. 2026-06-01 13:50 UTCEPSS rescore
  30. 2026-05-31 00:15 UTCEPSS rescore
  31. 2026-05-31 00:14 UTCEPSS rescore
  32. 2026-05-29 13:42 UTCEPSS rescore
  33. 2026-05-29 13:42 UTCEPSS rescore
  34. 2026-05-28 13:43 UTCEPSS rescore
  35. 2026-05-28 13:43 UTCEPSS rescore
  36. 2026-05-27 03:29 UTCEG score recompute
  37. 2026-05-27 03:29 UTCGHSA enrichment

Publicly available exploits

(2 references)

Working exploit code is in the public domain (1 Metasploit module) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Exploit-DBEDB-48513✓ verified
    First seen May 25, 2020

    Plesk/myLittleAdmin - ViewState .NET Deserialization (Metasploit)

    Open source ↗
  • Metasploitexploit/windows/http/plesk_mylittleadmin_viewstate✓ verified
    First seen May 15, 2020

    Plesk/myLittleAdmin ViewState .NET Deserialization

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2020-13166?
CVE-2020-13166 is a critical vulnerability published on May 19, 2020. The management tool in MyLittleAdmin 3.8 allows remote attackers to execute arbitrary code because machineKey is hardcoded (the same for all customers' installations) in web.config, and can be used to send serialized ASP code.
When was CVE-2020-13166 disclosed?
CVE-2020-13166 was first published in the National Vulnerability Database on May 19, 2020, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2020-13166 actively exploited?
CVE-2020-13166 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-13166?
CVE-2020-13166 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2020-13166?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-13166, 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.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2020-13166

Explore →

Is Your Infrastructure Affected by CVE-2020-13166?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs