Critical severity · published Jul 20, 2026
CVE-2026-39878
Chamilo stored XSS via user registration leads to admin account takeover
9.3
CVSS
0.4%
EPSS
No
On KEV
Description
Chamilo LMS versions 1.11.38 and earlier contain a stored cross-site scripting vulnerability in the user registration form that allows any unauthenticated attacker to execute arbitrary JavaScript in an administrator's browser session, leading to full platform admin account takeover. This has been patched in 1.11.40.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CH
chamilo-lms · chamilo
<= 1.11.38 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-39878
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-39878
github.com
https://github.com/chamilo/chamilo-lms/security/advisories/GHSA-gcjp-f7jm-rrrg
vokecyber.com
https://vokecyber.com/research/cve-2026-39878-chamilo-lms-stored-xss
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