CVE-2016-2555

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.
  • High exploitation likelihood — EPSS 80%
  • Public exploit code is available (Metasploit, Exploit-DB (verified), epss top5pct, epss high, public exploit)
CISA-KEV: Not listedEPSS PROB: 80%CVSS: 9.8Exploit: Metasploit · Exploit-DB (verified) · 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.

SQL injection vulnerability in include/lib/mysql_connect.inc.php in ATutor 2.2.1 allows remote attackers to execute arbitrary SQL commands via the searchFriends function to friends.inc.php.

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%
Exploitation80% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
80%
EPSS %ILE
100%
KEV
Not listed

Published

April 13, 2017

Last Modified

June 17, 2026

Advisory Details (4)

Auto-updated Sep 23, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit.
generic🟡 PoC Available

ATutor 2.2.1 - SQL Injection / Remote Code Execution (Metasploit) - PHP remote Exploit

https://www.exploit-db.com/exploits/39514/
github_commit Patch Available

commit 945a9dca01de (atutor/ATutor)

Patch available: atutor/ATutor atutor_2_2_2 (contains commit 945a9dca01de)

https://github.com/atutor/ATutor/commit/945a9dca01def8536516088da30fe6a4b7e9fa85
github_commit Patch Available

commit 629b2c992447 (atutor/ATutor)

Patch available: atutor/ATutor atutor_2_2_2 (contains commit 629b2c992447)

https://github.com/atutor/ATutor/commit/629b2c992447f7670a2fecc484abfad8c4c2d298
generic

ATutor 2.2.1 SQL Injection / Remote Code Execution | Metasploit Module

http://www.rapid7.com/db/modules/exploit/multi/http/atutor_sqli

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 4× in last 7d / 11× 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. 2026-09-15 00:14 UTCOSV refresh
  6. 2026-09-13 16:41 UTCEPSS rescore
  7. 2026-09-12 14:55 UTCEPSS rescore
  8. 2026-09-10 09:26 UTCEPSS rescore
  9. 2026-08-30 19:12 UTCEPSS rescore
  10. 2026-08-26 23:39 UTCOSV refresh
  11. 2026-08-26 14:41 UTCEPSS rescore
  12. 2026-08-25 13:44 UTCEPSS rescore
  13. 2026-08-21 23:44 UTCEPSS rescore
  14. 2026-08-19 16:59 UTCEPSS rescore
  15. 2026-08-16 02:09 UTCEPSS rescore
  16. 2026-08-15 01:25 UTCEPSS rescore
  17. 2026-08-12 13:46 UTCEPSS rescore
  18. 2026-08-10 13:40 UTCOSV refresh
  19. 2026-08-02 02:22 UTCEPSS rescore
  20. 2026-07-30 16:23 UTCEPSS rescore
  21. 2026-07-30 01:26 UTCEPSS rescore
  22. 2026-07-28 15:31 UTCEPSS rescore
  23. 2026-07-25 14:30 UTCOSV refresh
  24. 2026-07-25 14:13 UTCEPSS rescore
  25. 2026-07-23 14:14 UTCEPSS rescore
Show 61 more
  1. 2026-07-23 01:22 UTCEG score recompute
  2. 2026-07-22 22:02 UTCEG score recompute
  3. 2026-07-22 14:04 UTCEPSS rescore
  4. 2026-07-21 15:21 UTCEPSS rescore
  5. 2026-07-21 15:21 UTCEPSS rescore
  6. 2026-07-19 02:26 UTCEPSS rescore
  7. 2026-07-19 02:26 UTCEPSS rescore
  8. 2026-07-15 16:54 UTCEPSS rescore
  9. 2026-07-15 16:54 UTCEPSS rescore
  10. 2026-07-13 06:09 UTCEPSS rescore
  11. 2026-07-11 08:23 UTCEPSS rescore
  12. 2026-07-08 09:27 UTCOSV refresh
  13. 2026-07-06 02:20 UTCEPSS rescore
  14. 2026-07-06 02:20 UTCEPSS rescore
  15. 2026-06-30 23:19 UTCEPSS rescore
  16. 2026-06-27 03:05 UTCEPSS rescore
  17. 2026-06-27 03:05 UTCEPSS rescore
  18. 2026-06-25 13:47 UTCEPSS rescore
  19. 2026-06-25 13:47 UTCEPSS rescore
  20. 2026-06-23 21:30 UTCEPSS rescore
  21. 2026-06-19 21:06 UTCOSV refresh
  22. 2026-06-17 17:50 UTCEPSS rescore
  23. 2026-06-17 17:50 UTCEPSS rescore
  24. 2026-06-16 17:50 UTCEPSS rescore
  25. 2026-06-16 17:50 UTCEPSS rescore
  26. 2026-06-15 17:45 UTCEPSS rescore
  27. 2026-06-12 23:09 UTCEPSS rescore
  28. 2026-06-12 23:09 UTCEPSS rescore
  29. 2026-06-11 13:57 UTCEPSS rescore
  30. 2026-06-10 22:15 UTCEPSS rescore
  31. 2026-06-07 15:22 UTCEPSS rescore
  32. 2026-06-07 15:22 UTCEPSS rescore
  33. 2026-06-06 13:45 UTCEPSS rescore
  34. 2026-06-05 22:44 UTCEPSS rescore
  35. 2026-06-05 06:08 UTCEPSS rescore
  36. 2026-06-05 06:08 UTCEPSS rescore
  37. 2026-05-31 00:55 UTCOSV refresh
  38. 2026-05-31 00:14 UTCEPSS rescore
  39. 2026-05-28 13:42 UTCEPSS rescore
  40. 2026-05-28 13:42 UTCEPSS rescore
  41. 2026-05-27 13:38 UTCEPSS rescore
  42. 2026-05-27 13:38 UTCEPSS rescore
  43. 2026-05-26 07:16 UTCEPSS rescore
  44. 2026-05-24 16:43 UTCEPSS rescore
  45. 2026-05-22 21:15 UTCEPSS rescore
  46. 2026-05-22 21:15 UTCEPSS rescore
  47. 2026-05-20 22:37 UTCEPSS rescore
  48. 2026-05-20 22:37 UTCEPSS rescore
  49. 2026-05-20 22:37 UTCEPSS rescore
  50. 2026-05-20 10:07 UTCGHSA enrichment
  51. 2026-05-20 06:19 UTCGHSA enrichment
  52. 2026-05-20 02:31 UTCGHSA enrichment
  53. 2026-05-19 22:42 UTCGHSA enrichment
  54. 2026-05-19 18:54 UTCGHSA enrichment
  55. 2026-05-19 15:06 UTCGHSA enrichment
  56. 2026-05-19 11:17 UTCGHSA enrichment
  57. 2026-05-19 07:17 UTCGHSA enrichment
  58. 2026-05-19 03:29 UTCGHSA enrichment
  59. 2026-05-18 23:40 UTCEG score recompute
  60. 2026-05-18 21:30 UTCEPSS rescore
  61. 2026-05-18 21:30 UTCEPSS rescore

Publicly available exploits

(4 references)

Working exploit code is in the public domain (2 Metasploit modules) (1 GitHub PoC) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCshadofren/CVE-2016-2555
    First seen Aug 9, 2020

    CVE-2016-2555

    Open source ↗
  • Exploit-DBEDB-39514✓ verified
    First seen Mar 1, 2016

    ATutor 2.2.1 - SQL Injection / Remote Code Execution (Metasploit)

    Open source ↗
  • Metasploitexploit/multi/http/atutor_sqli✓ verified
    First seen Mar 1, 2016

    ATutor 2.2.1 SQL Injection / Remote Code Execution

    Open source ↗
  • Metasploitexploit/linux/http/atutor_filemanager_traversal✓ verified
    First seen Mar 1, 2016

    ATutor 2.2.1 Directory Traversal / Remote Code Execution

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2016-2555?
CVE-2016-2555 is a critical vulnerability published on April 13, 2017. SQL injection vulnerability in include/lib/mysql_connect.inc.php in ATutor 2.2.1 allows remote attackers to execute arbitrary SQL commands via the searchFriends function to friends.inc.php.
When was CVE-2016-2555 disclosed?
CVE-2016-2555 was first published in the National Vulnerability Database on April 13, 2017, 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-2016-2555 actively exploited?
CVE-2016-2555 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 80% 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-2016-2555?
CVE-2016-2555 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2016-2555?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-2555, 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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