CVE-2023-4220
MediumExploitedPublic exploitUnrestricted 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…
Published Nov 28, 2023 · Updated Aug 12, 2026
Key Facts
Patch immediately- CVE-2023-4220 is a medium-severity vulnerability (CVSS 6.1 v3.1) affecting Chamilo Lms, Chamilo.
- It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Nov 28, 2023. Public exploit code is available.
- EPSS estimates a 76% probability of exploitation in the next 30 days.
- Fixed versions are available, including Chamilo Lms <=1.11.24, Chamilo Lms 1.11.24.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
6.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS (30-day exploit likelihood)
76%
Higher than 99.5% of all scored CVEs
Exploited in the wild
Yes
2 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2023-4220 brief as a PDF
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Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Dec 5, 2024 | n/a | Not reported |
| CIRCL KEV | Nov 28, 2023 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Chamilo LmsChamilo | See advisory | 1.11.24 |
| Chamilo | See advisory | n/a |
Patched Releases
Chamilo Lms
<=1.11.24
Timeline
Publicly disclosed
Nov 28, 2023
Added to CIRCL KEV
Nov 28, 2023
Added to Industry KEV feed
Dec 5, 2024
Last updated
Aug 12, 2026
Weakness Type
- CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
- advisoryhttps://github.com/CVEProject/cvelistV5/tree/main/cves/2023/4xxx/CVE-2023-4220.json
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2023-4220
- advisoryhttps://support.chamilo.org/projects/chamilo-18/wiki/security_issues#Issue-130-2023-09-04-Critical-impact-High-risk-Unauthenticated-users-may-gain-XSS-and-unauthenticated-RCE-CVE-2023-4220
- patchhttps://github.com/chamilo/chamilo-lms/commit/3b487a55076fb06f96809b790a35dcdd42f8ec49
- exploitVulnCheck exploitation report
FAQ
Common Questions.
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.
Affected: Chamilo Lms; Chamilo. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Nov 28, 2023.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Chamilo Lms <=1.11.24, Chamilo Lms 1.11.24.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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