CVE-2016-8870

HIGHNVD 8.18.9
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 8.9 because EPSS predicted 81% probability of exploitation within the next 30 days (99th percentile of EPSS-scored CVEs) when EchelonGraph scored this CVE. NVD baseline CVSS 8.1 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction (continuous uplift above 30%)
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this weekWeaponized

Also known asEUVD-2016-9695 (ENISA EUVD) · GHSA-f3v8-7jfc-xgvg (GitHub Security Advisories)Source: ENISA EUVD

8.9EG
EchelonGraph verdictPlan mitigationThe upstream fix is not in a release yet: until the release ships, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high, then apply it (the SSVC decision on this page).
  • High exploitation likelihood — EPSS 81%
  • Public exploit code is available (Metasploit, other public proof-of-concept code)
CISA-KEV: Not listedEPSS PROB: 81%CVSS: 8.1Exploit: Metasploit · other public PoCExposed services: Not assessed

An upstream fix is merged but not yet released — mitigate (WAF / firewall / segmentation) until the release ships, then apply it.

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
8.9HIGHhigh confidence
EG Risk
69
EG Risk 69/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity81% × 45%
Impact severity (EG Severity): CVSS 8.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation81% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's BOD 26-04 default: no one has published Automatable for this CVE, and CISA treats it as “no” for a CVE not in KEV.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: An upstream fix is merged but not yet in a tagged release. Until the release ships, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high, then apply it.
EPSS PROB
81%
EPSS %ILE
99th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (8.9): severity, escalated by confirmed exploitation. This CVE's 8.9 is EPSS's lift toward 9.0 from its impact severity (EG Severity, CVSS 8.1 HIGH): a likelihood of exploitation, not impact.

EG Severity
8.1 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
81% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

An upstream fix is merged but not yet in a tagged release. Until the release ships, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high, then apply it.

Exploitation public PoC (exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

November 4, 2016

Last Modified

June 17, 2026

Advisory Details (6)

Auto-updated Sep 19, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit.
Web page

Joomla Account Creation and Privilege Escalation | Metasploit Module

http://www.rapid7.com/db/modules/auxiliary/admin/http/joomla_registration_privesc
Web page

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
Web page

Details on the Privilege Escalation Vulnerability in Joomla

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

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 7× in last 7d / 23× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 13 repeat rows among the latest 100 are merged into the row they repeat.

  1. 2026-10-31 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  2. 2026-10-29 22:48 UTCEG score recompute
  3. 2026-10-29 22:48 UTCGHSA enrichmentGHSA-f3v8-7jfc-xgvg · GitHub severity HIGH · GitHub CVSS 8.1
  4. 2026-10-29 16:55 UTCOSV refresh
  5. 2026-10-29 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  6. 2026-10-28 16:26 UTCEPSS rescoreEPSS 81% · 99th percentile
  7. 2026-10-27 16:26 UTCEPSS rescoreEPSS 81% · 99th percentile
  8. 2026-10-25 19:43 UTCEG score recompute
  9. 2026-10-25 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  10. 2026-10-22 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  11. 2026-10-22 07:20 UTCEG score recompute
  12. 2026-10-22 07:19 UTCGHSA enrichmentGHSA-f3v8-7jfc-xgvg · GitHub severity HIGH · GitHub CVSS 8.1
  13. 2026-10-21 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  14. 2026-10-18 10:45 UTCEG score recompute
  15. 2026-10-17 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  16. 2026-10-14 16:27 UTCEPSS rescoreEPSS 81% · 99th percentile
  17. 2026-10-13 03:19 UTCGHSA enrichmentGHSA-f3v8-7jfc-xgvg · GitHub severity HIGH · GitHub CVSS 8.1
  18. 2026-10-12 20:39 UTCEG score recompute
  19. 2026-10-12 01:02 UTCEG score recompute
  20. 2026-10-09 20:01 UTCEPSS rescoreEPSS 81% · 99th percentile
  21. 2026-10-08 13:05 UTCOSV refresh
  22. 2026-10-07 23:40 UTCEPSS rescoreEPSS 81% · 99th percentile
  23. 2026-10-06 15:11 UTCEPSS rescoreEPSS 81% · 99th percentile
  24. 2026-09-30 14:58 UTCEPSS rescoreEPSS 81% · 99th percentile
  25. 2026-09-30 09:17 UTCEG score recompute▼ 0.10
Show 62 more
  1. 2026-09-26 15:53 UTCEPSS rescoreEPSS 81% · 99th percentile
  2. 2026-09-24 13:59 UTCEPSS rescoreEPSS 81% · 99th percentile
  3. 2026-09-23 13:41 UTCEPSS rescoreEPSS 81% · 99th percentile
  4. 2026-09-19 15:35 UTCEPSS rescoreEPSS 81% · 99th percentile
  5. 2026-09-18 19:22 UTCEPSS rescoreEPSS 81% · 99th percentile
  6. 2026-09-18 18:50 UTCOSV refresh
  7. 2026-09-17 19:22 UTCEPSS rescoreEPSS 81% · 99th percentile
  8. 2026-09-16 05:05 UTCEPSS rescoreEPSS 81% · 99th percentile
  9. 2026-09-12 14:55 UTCEPSS rescoreEPSS 81% · 99th percentile
  10. 2026-09-10 09:26 UTCEPSS rescoreEPSS 81% · 99th percentile
  11. 2026-09-07 15:56 UTCEPSS rescoreEPSS 81% · 99th percentile
  12. 2026-09-04 13:56 UTCEPSS rescoreEPSS 81% · 99th percentile
  13. 2026-09-01 13:48 UTCEPSS rescoreEPSS 81% · 99th percentile
  14. 2026-08-30 22:04 UTCOSV refresh
  15. 2026-08-28 21:35 UTCEPSS rescoreEPSS 83% · 99th percentile
  16. 2026-08-26 14:41 UTCEPSS rescoreEPSS 81% · 99th percentile
  17. 2026-08-25 13:44 UTCEPSS rescoreEPSS 81% · 99th percentile
  18. 2026-08-19 16:59 UTCEPSS rescoreEPSS 81% · 99th percentile
  19. 2026-08-16 02:10 UTCEPSS rescoreEPSS 81% · 99th percentile
  20. 2026-08-15 01:25 UTCEPSS rescoreEPSS 81% · 99th percentile
  21. 2026-08-14 08:46 UTCOSV refresh
  22. 2026-08-12 13:46 UTCEPSS rescoreEPSS 81% · 99th percentile
  23. 2026-08-05 19:12 UTCEPSS rescoreEPSS 81% · 99th percentile
  24. 2026-07-29 17:07 UTCOSV refresh
  25. 2026-07-26 14:50 UTCEPSS rescoreEPSS 81% · 99th percentile
  26. 2026-07-24 14:13 UTCEPSS rescoreEPSS 81% · 99th percentile
  27. 2026-07-23 14:15 UTCEPSS rescoreEPSS 81% · 99th percentile
  28. 2026-07-23 01:24 UTCEG score recompute▲ 0.90
  29. 2026-07-22 22:04 UTCEG score recompute▼ 0.90
  30. 2026-07-22 14:04 UTCEPSS rescoreEPSS 82% · 99th percentile
  31. 2026-07-20 17:04 UTCEPSS rescoreEPSS 82% · 99th percentile
  32. 2026-07-16 16:59 UTCEPSS rescoreEPSS 82% · 99th percentile
  33. 2026-07-15 16:54 UTCEPSS rescoreEPSS 82% · 99th percentile
  34. 2026-07-13 22:26 UTCEPSS rescoreEPSS 82% · 99th percentile
  35. 2026-07-12 06:37 UTCOSV refresh
  36. 2026-07-09 19:06 UTCEPSS rescoreEPSS 82% · 99th percentile
  37. 2026-07-06 02:20 UTCEPSS rescoreEPSS 82% · 99th percentile
  38. 2026-07-04 06:28 UTCEPSS rescoreEPSS 82% · 99th percentile
  39. 2026-07-01 15:02 UTCEPSS rescoreEPSS 82% · 99th percentile
  40. 2026-06-25 13:47 UTCEPSS rescoreEPSS 82% · 99th percentile
  41. 2026-06-24 14:02 UTCEPSS rescoreEPSS 82% · 99th percentile
  42. 2026-06-23 21:30 UTCEPSS rescoreEPSS 82% · 99th percentile
  43. 2026-06-23 12:28 UTCOSV refresh
  44. 2026-06-21 01:57 UTCEPSS rescoreEPSS 82% · 99th percentile
  45. 2026-06-16 17:50 UTCEPSS rescoreEPSS 82% · 99th percentile
  46. 2026-06-15 17:45 UTCEPSS rescoreEPSS 82% · 99th percentile
  47. 2026-06-12 23:09 UTCEPSS rescoreEPSS 92% · 99th percentile
  48. 2026-06-08 14:14 UTCEPSS rescoreEPSS 92% · 99th percentile
  49. 2026-06-07 15:22 UTCEPSS rescoreEPSS 92% · 99th percentile
  50. 2026-06-06 14:29 UTCOSV refresh
  51. 2026-06-06 13:45 UTCEPSS rescoreEPSS 92% · 99th percentile
  52. 2026-06-05 22:44 UTCEPSS rescoreEPSS 92% · 99th percentile
  53. 2026-06-02 20:10 UTCEPSS rescoreEPSS 92% · 99th percentile
  54. 2026-05-31 22:28 UTCEPSS rescoreEPSS 92% · 99th percentile
  55. 2026-05-28 13:42 UTCEPSS rescoreEPSS 92% · 99th percentile
  56. 2026-05-26 13:42 UTCEPSS rescoreEPSS 92% · 99th percentile
  57. 2026-05-24 16:44 UTCEPSS rescoreEPSS 92% · 99th percentile
  58. 2026-05-22 21:15 UTCEPSS rescoreEPSS 92% · 99th percentile
  59. 2026-05-22 18:03 UTCEG score recompute
  60. 2026-05-22 18:03 UTCGHSA enrichmentGHSA-f3v8-7jfc-xgvg · GitHub severity HIGH · GitHub CVSS 8.1
  61. 2026-05-20 11:21 UTCEPSS rescoreEPSS 92% · 99th percentile
  62. 2026-05-18 21:30 UTCEPSS rescoreEPSS 92% · 99th percentile

Publicly available exploits

(2 references)

Public exploit code is referenced for this CVE (1 Metasploit module, 1 Exploit-DB entry). The fix is not yet in a release, so defenders should restrict or isolate affected systems accordingly until it ships.

  • Metasploitauxiliary/admin/http/joomla_registration_privesc✓ verified
    Published Nov 2, 2016

    Joomla Account Creation and Privilege Escalation

    Open source ↗
  • Exploit-DBEDB-40637
    Published Oct 27, 2016

    Joomla! 3.4.4 < 3.6.4 - Account Creation / Privilege Escalation

    Open source ↗

Frequently asked(5)

What is CVE-2016-8870?
CVE-2016-8870 is a high-severity vulnerability; its CVE record was 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 made public?
CVE-2016-8870 was made public on October 25, 2016: that is the date its CVE record's CNA, MITRE Corporation, gives for when the vulnerability was made public. The CVE record itself was published on November 4, 2016. EchelonGraph's copy of the record carries a last-modified date of June 17, 2026; the record at its source may have been updated since.
Is CVE-2016-8870 actively exploited?
CVE-2016-8870 is not currently on CISA's Known Exploited Vulnerabilities catalog. EchelonGraph's EG-KEV model places it in Tier 2 (Weaponized), which is not evidence of exploitation: a Metasploit module exists for it. EchelonGraph does not test whether exploit code works. FIRST EPSS estimates a 81% probability of exploitation in the next 30 days (99th percentile of EPSS-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 + FIRST EPSS + GHSA into a combined EG score of 8.9 (HIGH).
How do I remediate CVE-2016-8870?
An upstream fix for CVE-2016-8870 has been merged but is not yet in a tagged release. Until it ships, restrict network exposure of the affected system or apply the vendor's mitigation, then update to the release that contains the fix.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2016-8870

Explore →

Is Your Infrastructure Affected by CVE-2016-8870?

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