CVE-2023-4220

MEDIUMNVD 6.18.9▲
EchelonGraph scoreHIGH confidence

Score elevated to 8.9 because EPSS predicts 76% probability of exploitation within the next 30 days (top 0.5% of all CVEs). NVD baseline CVSS 6.1 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction ≥85%
Sources: epss, ghsa, nvd
Weaponized
6.1
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 76%
CISA-KEV: Not listedEPSS: 76%CVSS: 6.1Exploit: NoneExposed: 0

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

Unrestricted file upload in big file upload functionality in /main/inc/lib/javascript/bigupload/inc/bigUpload.php in Chamilo LMS <= v1.11.24 allows unauthenticated attackers to perform stored cross-site scripting attacks and obtain remote code execution via uploading of web shell.

CVSS v3
6.1
EG Score
8.9(high)
EG Risk
75(Track)
EG Risk 75/100SSVC: 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
Severity89% × 45%
Exploitation76% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
99.5%
KEV
Not listed

Published

November 28, 2023

Last Modified

June 17, 2026

References (6)

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 28× 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. 2026-07-24 14:16 UTCEPSS rescore
  2. 2026-07-24 14:16 UTCEPSS rescore
  3. 2026-07-23 02:26 UTCEG score recompute▲ 0.80
  4. 2026-07-22 23:13 UTCEG score recompute▼ 0.90
  5. 2026-07-22 14:06 UTCEPSS rescore
  6. 2026-07-21 15:23 UTCEPSS rescore
  7. 2026-07-21 15:23 UTCEPSS rescore
  8. 2026-07-20 17:06 UTCEPSS rescore
  9. 2026-07-16 17:01 UTCEPSS rescore
  10. 2026-07-15 16:56 UTCEPSS rescore
  11. 2026-07-15 16:56 UTCEPSS rescore
  12. 2026-07-15 02:49 UTCOSV refresh
  13. 2026-07-13 22:28 UTCEPSS rescore
  14. 2026-07-13 22:28 UTCEPSS rescore
  15. 2026-07-12 05:45 UTCEPSS rescore
  16. 2026-07-11 08:26 UTCEPSS rescore
  17. 2026-07-07 13:44 UTCEPSS rescore
  18. 2026-07-07 13:44 UTCEPSS rescore
  19. 2026-07-04 06:29 UTCEPSS rescore
  20. 2026-07-04 06:29 UTCEPSS rescore
  21. 2026-07-01 15:05 UTCEPSS rescore
  22. 2026-06-30 23:21 UTCEPSS rescore
  23. 2026-06-30 23:21 UTCEPSS rescore
  24. 2026-06-29 14:05 UTCEPSS rescore
  25. 2026-06-28 04:55 UTCEPSS rescore
Show 32 more
  1. 2026-06-27 03:34 UTCOSV refresh
  2. 2026-06-25 13:48 UTCEPSS rescore
  3. 2026-06-25 13:48 UTCEPSS rescore
  4. 2026-06-24 14:04 UTCEPSS rescore
  5. 2026-06-24 14:04 UTCEPSS rescore
  6. 2026-06-24 06:31 UTCNVD updateCVSS v3 → 6.1 · severity → MEDIUM
  7. 2026-06-23 21:31 UTCEPSS rescore
  8. 2026-06-23 21:31 UTCEPSS rescore
  9. 2026-06-21 01:58 UTCEPSS rescore
  10. 2026-06-21 01:58 UTCEPSS rescore
  11. 2026-06-19 19:24 UTCEPSS rescore
  12. 2026-06-19 19:24 UTCEPSS rescore
  13. 2026-06-17 17:51 UTCEPSS rescore
  14. 2026-06-15 17:47 UTCEPSS rescore
  15. 2026-06-12 23:11 UTCEPSS rescore
  16. 2026-06-12 23:10 UTCEPSS rescore
  17. 2026-06-11 13:59 UTCEPSS rescore
  18. 2026-06-09 14:17 UTCOSV refresh
  19. 2026-06-08 14:16 UTCEPSS rescore
  20. 2026-06-08 14:16 UTCEPSS rescore
  21. 2026-06-02 20:12 UTCEPSS rescore
  22. 2026-06-02 20:12 UTCEPSS rescore
  23. 2026-06-01 13:51 UTCEPSS rescore
  24. 2026-06-01 13:51 UTCEPSS rescore
  25. 2026-05-28 13:44 UTCEPSS rescore
  26. 2026-05-27 13:39 UTCEPSS rescore
  27. 2026-05-27 13:39 UTCEPSS rescore
  28. 2026-05-26 13:43 UTCEPSS rescore
  29. 2026-05-26 13:43 UTCEPSS rescore
  30. 2026-05-24 13:14 UTCEG score recompute
  31. 2026-05-24 13:14 UTCGHSA enrichment
  32. 2026-05-23 20:35 UTCOSV refresh

Publicly available exploits

(5 references)

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

  • Exploit-DBEDB-52083
    First seen Mar 18, 2025

    Chamilo LMS 1.11.24 - Remote Code Execution (RCE)

    Open source ↗
  • GitHub PoCZiad-Sakr/Chamilo-CVE-2023-4220-Exploit
    First seen Jul 8, 2024

    This is an Exploit for Unrestricted file upload in big file upload functionality in Chamilo-LMS for this location "/main/inc/lib/javascript/bigupload/inc/bigUpload.php" in Chamilo LMS <= v1.11.24, and Attackers can obtain remote code execution via uploading of web shell.

    Open source ↗
  • GitHub PoCRai2en/CVE-2023-4220-Chamilo-LMS
    First seen Jul 7, 2024

    This is a script written in Python that allows the exploitation of the Chamilo's LMS software security flaw described in CVE-2023-4220

    Open source ↗
  • Metasploitexploit/linux/http/chamilo_bigupload_webshell✓ verified
    First seen Nov 28, 2023

    Chamilo v1.11.24 Unrestricted File Upload PHP Webshell

    Open source ↗
  • Nucleihttp/cves/2023/CVE-2023-4220.yaml
    First seen Jan 1, 2023

    Chamilo LMS <= 1.11.24 - Remote Code Execution

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2023-4220?
CVE-2023-4220 is a medium vulnerability published on November 28, 2023. Unrestricted file upload in big file upload functionality in /main/inc/lib/javascript/bigupload/inc/bigUpload.php in Chamilo LMS <= v1.11.24 allows unauthenticated attackers to perform stored cross-site scripting attacks and obtain remote code execution via uploading of web shell.
When was CVE-2023-4220 disclosed?
CVE-2023-4220 was first published in the National Vulnerability Database on November 28, 2023, 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-2023-4220 actively exploited?
CVE-2023-4220 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-2023-4220?
CVE-2023-4220 has a CVSS v3 base score of 6.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.9.
How do I remediate CVE-2023-4220?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-4220, 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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