CVE-2016-1909

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2022-05-17. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Weaponized
9.8EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • 41 internet-exposed hosts are running an affected version right now
  • High exploitation likelihood — EPSS 71%
  • Public exploit code is available (Metasploit, epss top5pct, epss high, public exploit)
CISA-KEV: Not listedEPSS PROB: 71%CVSS: 9.8Exploit: Metasploit · epss top5pct · epss high · public exploitExposed: 41

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

Fortinet FortiAnalyzer before 5.0.12 and 5.2.x before 5.2.5; FortiSwitch 3.3.x before 3.3.3; FortiCache 3.0.x before 3.0.8; and FortiOS 4.1.x before 4.1.11, 4.2.x before 4.2.16, 4.3.x before 4.3.17 and 5.0.x before 5.0.8 have a hardcoded passphrase for the Fortimanager_Access account, which allows remote attackers to obtain administrative access via an SSH session.

Live · internet exposure

41 internet-exposed hosts are running an affected version of CVE-2016-1909 right now.

across 18 countries (United States, Hong Kong, Thailand, Australia, France)top: fortios
See the live KEV-Exposure radar →Found passively from public internet-scan data — aggregate, host-redacted.

EchelonGraph is the only CVE feed that fuses live vulnerability intelligence with its own live internet-exposure radar — so you see not just that a CVE is exploited, but how much of the internet is exposed to it right now.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
77(Track*)
EG Risk 77/100SSVC: 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%
Exploitation71% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
71%
EPSS %ILE
99%
KEV
Not listed

Published

January 15, 2016

Last Modified

June 17, 2026

Advisory Details (3)

Auto-updated Jul 27, 2026
No patch confirmed yet.
generic

Full Disclosure: SSH Backdoor for FortiGate OS Version 4.x up to 5.0.7

http://seclists.org/fulldisclosure/2016/Jan/26
generic

RPW: @[email protected] on X: "SSH backdoors/bugdoors seem to become a pattern lately: https://t.co/RdlQxWyCRv. This edition sponsored by Fortinet." / X

https://twitter.com/esizkur/status/686842135501508608
generic
http://www.securitytracker.com/id/1034663

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 16× 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. 2026-07-26 14:50 UTCEPSS rescore
  2. 2026-07-23 14:14 UTCEPSS rescore
  3. 2026-07-23 01:22 UTCEG score recompute
  4. 2026-07-22 22:01 UTCEG score recompute
  5. 2026-07-22 14:04 UTCEPSS rescore
  6. 2026-07-20 17:03 UTCEPSS rescore
  7. 2026-07-19 14:27 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. 2026-07-13 06:09 UTCEPSS rescore
  12. 2026-07-11 08:23 UTCEPSS rescore
  13. 2026-07-09 19:05 UTCEPSS rescore
  14. 2026-07-08 15:10 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. 2026-06-25 13:47 UTCEPSS rescore
  19. 2026-06-24 14:02 UTCEPSS rescore
  20. 2026-06-24 14:02 UTCEPSS rescore
  21. 2026-06-23 21:30 UTCEPSS rescore
  22. 2026-06-21 01:57 UTCEPSS rescore
  23. 2026-06-21 01:57 UTCEPSS rescore
  24. 2026-06-18 17:50 UTCEPSS rescore
  25. 2026-06-17 17:50 UTCEPSS rescore
Show 46 more
  1. 2026-06-17 17:50 UTCEPSS rescore
  2. 2026-06-16 17:50 UTCEPSS rescore
  3. 2026-06-16 17:50 UTCEPSS rescore
  4. 2026-06-15 17:45 UTCEPSS rescore
  5. 2026-06-13 22:57 UTCEPSS rescore
  6. 2026-06-13 22:57 UTCEPSS rescore
  7. 2026-06-12 23:09 UTCEPSS rescore
  8. 2026-06-12 23:09 UTCEPSS rescore
  9. 2026-06-10 22:15 UTCEPSS rescore
  10. 2026-06-10 13:18 UTCEPSS rescore
  11. 2026-06-08 14:14 UTCEPSS rescore
  12. 2026-06-07 15:22 UTCEPSS rescore
  13. 2026-06-07 15:22 UTCEPSS rescore
  14. 2026-06-06 13:45 UTCEPSS rescore
  15. 2026-06-05 22:44 UTCEPSS rescore
  16. 2026-06-05 06:08 UTCEPSS rescore
  17. 2026-06-05 06:08 UTCEPSS rescore
  18. 2026-06-02 20:10 UTCEPSS rescore
  19. 2026-06-01 13:49 UTCEPSS rescore
  20. 2026-06-01 13:49 UTCEPSS rescore
  21. 2026-05-31 22:28 UTCEPSS rescore
  22. 2026-05-31 22:28 UTCEPSS rescore
  23. 2026-05-31 00:14 UTCEPSS rescore
  24. 2026-05-28 13:42 UTCEPSS rescore
  25. 2026-05-28 13:42 UTCEPSS rescore
  26. 2026-05-26 07:16 UTCEPSS rescore
  27. 2026-05-22 21:15 UTCEPSS rescore
  28. 2026-05-22 21:15 UTCEPSS rescore
  29. 2026-05-20 22:37 UTCEPSS rescore
  30. 2026-05-20 22:37 UTCEPSS rescore
  31. 2026-05-20 22:37 UTCEPSS rescore
  32. 2026-05-20 11:21 UTCEPSS rescore
  33. 2026-05-20 11:21 UTCEPSS rescore
  34. 2026-05-20 11:21 UTCEPSS rescore
  35. 2026-05-20 09:40 UTCGHSA enrichment
  36. 2026-05-20 05:33 UTCGHSA enrichment
  37. 2026-05-20 01:26 UTCGHSA enrichment
  38. 2026-05-19 21:19 UTCGHSA enrichment
  39. 2026-05-19 17:06 UTCGHSA enrichment
  40. 2026-05-19 12:59 UTCGHSA enrichment
  41. 2026-05-19 08:51 UTCGHSA enrichment
  42. 2026-05-19 04:44 UTCGHSA enrichment
  43. 2026-05-19 00:37 UTCEG score recompute
  44. 2026-05-19 00:37 UTCGHSA enrichment
  45. 2026-05-18 21:30 UTCEPSS rescore
  46. 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-43386
    First seen Jan 9, 2016

    Fortinet FortiGate 4.x < 5.0.7 - SSH Backdoor Access

    Open source ↗
  • Metasploitauxiliary/scanner/ssh/fortinet_backdoor✓ verified
    First seen Jan 9, 2016

    Fortinet SSH Backdoor Scanner

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2016-1909?
CVE-2016-1909 is a critical vulnerability published on January 15, 2016. Fortinet FortiAnalyzer before 5.0.12 and 5.2.x before 5.2.5; FortiSwitch 3.3.x before 3.3.3; FortiCache 3.0.x before 3.0.8; and FortiOS 4.1.x before 4.1.11, 4.2.x before 4.2.16, 4.3.x before 4.3.17 and 5.0.x before 5.0.8 have a hardcoded passphrase for the Fortimanager_Access account, which allows…
When was CVE-2016-1909 disclosed?
CVE-2016-1909 was first published in the National Vulnerability Database on January 15, 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-2016-1909 actively exploited?
CVE-2016-1909 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 71% probability of exploitation in the next 30 days, which ranks it in the top 0.7% of all scored CVEs.
What is the CVSS score of CVE-2016-1909?
CVE-2016-1909 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2016-1909?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-1909, 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

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