CVE-2016-8870

CRITICALNVD 8.19.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because EPSS predicts 82% probability of exploitation within the next 30 days (top 0.4% of all CVEs). NVD baseline CVSS 8.1 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction ≥85%
Sources: epss, ghsa, nvd
Weaponized
9.0EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 81%
  • Public exploit code is available (Metasploit, epss top5pct, epss high, public exploit)
CISA-KEV: Not listedEPSS PROB: 81%CVSS: 8.1Exploit: Metasploit · epss top5pct · epss high · public exploitExposed: 0

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

The register method in the UsersModelRegistration class in controllers/user.php in the Users component in Joomla! before 3.6.4, when registration has been disabled, allows remote attackers to create user accounts by leveraging failure to check the Allow User Registration configuration setting.

CVSS v3
8.1
EG Score
9.0(high)
EG Risk
78(Track)
EG Risk 78/100SSVC: 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
Severity90% × 45%
Exploitation82% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
81%
EPSS %ILE
100%
KEV
Not listed

Published

November 4, 2016

Last Modified

June 17, 2026

Advisory Details (6)

Auto-updated Sep 19, 2026
⚠️ Active exploitation confirmed. Upstream fix merged — awaiting tagged release. Sources: github_commit.
generic

Joomla Account Creation and Privilege Escalation | Metasploit Module

http://www.rapid7.com/db/modules/auxiliary/admin/http/joomla_registration_privesc
generic🟡 PoC Available

Joomla! 3.4.4 < 3.6.4 - Account Creation / Privilege Escalation - PHP webapps Exploit

https://www.exploit-db.com/exploits/40637/
github_commit

commit bae1d43938c8 (joomla/joomla-cms)

Fix landed in joomla/joomla-cms commit bae1d43938c8 — awaiting tagged release

https://github.com/joomla/joomla-cms/commit/bae1d43938c878480cfd73671e4945211538fdcf
generic

[20161001] - Core - Account Creation

https://developer.joomla.org/security-centre/659-20161001-core-account-creation.html
generic🔴 Active Exploitation

Details on the Privilege Escalation Vulnerability in Joomla

https://blog.sucuri.net/2016/10/details-on-the-privilege-escalation-vulnerability-in-joomla.html
generic

CVE-2016-8870 - PSIRT.COM

http://www.securityfocus.com/bid/93876

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 15× 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. 2026-09-24 13:59 UTCEPSS rescore
  2. 2026-09-23 13:41 UTCEPSS rescore
  3. 2026-09-19 15:35 UTCEPSS rescore
  4. 2026-09-18 19:22 UTCEPSS rescore
  5. 2026-09-18 18:50 UTCOSV refresh
  6. 2026-09-17 19:22 UTCEPSS rescore
  7. 2026-09-16 05:05 UTCEPSS rescore
  8. 2026-09-12 14:55 UTCEPSS rescore
  9. 2026-09-10 09:26 UTCEPSS rescore
  10. 2026-09-07 15:56 UTCEPSS rescore
  11. 2026-09-04 13:56 UTCEPSS rescore
  12. 2026-09-01 13:48 UTCEPSS rescore
  13. 2026-08-30 22:04 UTCOSV refresh
  14. 2026-08-28 21:35 UTCEPSS rescore
  15. 2026-08-26 14:41 UTCEPSS rescore
  16. 2026-08-25 13:44 UTCEPSS rescore
  17. 2026-08-19 16:59 UTCEPSS rescore
  18. 2026-08-16 02:10 UTCEPSS rescore
  19. 2026-08-15 01:25 UTCEPSS rescore
  20. 2026-08-14 08:46 UTCOSV refresh
  21. 2026-08-12 13:46 UTCEPSS rescore
  22. 2026-08-05 19:12 UTCEPSS rescore
  23. 2026-07-29 17:07 UTCOSV refresh
  24. 2026-07-26 14:50 UTCEPSS rescore
  25. 2026-07-24 14:13 UTCEPSS rescore
Show 48 more
  1. 2026-07-23 14:15 UTCEPSS rescore
  2. 2026-07-23 01:24 UTCEG score recompute▲ 0.90
  3. 2026-07-22 22:04 UTCEG score recompute▼ 0.90
  4. 2026-07-22 14:04 UTCEPSS rescore
  5. 2026-07-20 17:04 UTCEPSS rescore
  6. 2026-07-16 16:59 UTCEPSS rescore
  7. 2026-07-16 16:59 UTCEPSS rescore
  8. 2026-07-15 16:54 UTCEPSS rescore
  9. 2026-07-15 16:54 UTCEPSS rescore
  10. 2026-07-13 22:26 UTCEPSS rescore
  11. 2026-07-12 06:37 UTCOSV refresh
  12. 2026-07-09 19:06 UTCEPSS rescore
  13. 2026-07-06 02:20 UTCEPSS rescore
  14. 2026-07-06 02:20 UTCEPSS rescore
  15. 2026-07-04 06:28 UTCEPSS rescore
  16. 2026-07-01 15:02 UTCEPSS rescore
  17. 2026-06-25 13:47 UTCEPSS rescore
  18. 2026-06-24 14:02 UTCEPSS rescore
  19. 2026-06-23 21:30 UTCEPSS rescore
  20. 2026-06-23 12:28 UTCOSV refresh
  21. 2026-06-21 01:57 UTCEPSS rescore
  22. 2026-06-21 01:57 UTCEPSS rescore
  23. 2026-06-16 17:50 UTCEPSS rescore
  24. 2026-06-15 17:45 UTCEPSS rescore
  25. 2026-06-12 23:09 UTCEPSS rescore
  26. 2026-06-08 14:14 UTCEPSS rescore
  27. 2026-06-07 15:22 UTCEPSS rescore
  28. 2026-06-07 15:22 UTCEPSS rescore
  29. 2026-06-06 14:29 UTCOSV refresh
  30. 2026-06-06 13:45 UTCEPSS rescore
  31. 2026-06-06 13:45 UTCEPSS rescore
  32. 2026-06-05 22:44 UTCEPSS rescore
  33. 2026-06-02 20:10 UTCEPSS rescore
  34. 2026-05-31 22:28 UTCEPSS rescore
  35. 2026-05-31 22:28 UTCEPSS rescore
  36. 2026-05-28 13:42 UTCEPSS rescore
  37. 2026-05-28 13:42 UTCEPSS rescore
  38. 2026-05-26 13:42 UTCEPSS rescore
  39. 2026-05-26 13:42 UTCEPSS rescore
  40. 2026-05-24 16:44 UTCEPSS rescore
  41. 2026-05-22 21:15 UTCEPSS rescore
  42. 2026-05-22 18:03 UTCEG score recompute
  43. 2026-05-22 18:03 UTCGHSA enrichment
  44. 2026-05-20 11:21 UTCEPSS rescore
  45. 2026-05-20 11:21 UTCEPSS rescore
  46. 2026-05-18 21:30 UTCEPSS rescore
  47. 2026-05-18 21:30 UTCEPSS rescore
  48. 2026-05-18 21:30 UTCEPSS rescore

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-40637
    First seen Oct 27, 2016

    Joomla! 3.4.4 < 3.6.4 - Account Creation / Privilege Escalation

    Open source ↗
  • Metasploitauxiliary/admin/http/joomla_registration_privesc✓ verified
    First seen Oct 25, 2016

    Joomla Account Creation and Privilege Escalation

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2016-8870?
CVE-2016-8870 is a critical vulnerability published on November 4, 2016. The register method in the UsersModelRegistration class in controllers/user.php in the Users component in Joomla! before 3.6.4, when registration has been disabled, allows remote attackers to create user accounts by leveraging failure to check the Allow User Registration configuration setting.
When was CVE-2016-8870 disclosed?
CVE-2016-8870 was first published in the National Vulnerability Database on November 4, 2016, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2016-8870 actively exploited?
CVE-2016-8870 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 81% probability of exploitation in the next 30 days, which ranks it in the top 0.4% of all scored CVEs.
What is the CVSS score of CVE-2016-8870?
CVE-2016-8870 has a CVSS v3 base score of 8.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
How do I remediate CVE-2016-8870?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-8870, 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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