CVE-2023-31799Network attack vector

Stored script execution via system announcements

Published May 9, 2023 · Updated Jul 9, 2026

Stored XSS in Chamilo LMS 1.11.18 allows remote authenticated users to execute script in another user’s browser via system announcements. The vendor identifies the system-announcement editor as accepting administrator-inserted XSS content but does not publish the faulty file, function, or encoding operation. Administrator privileges are required to plant the payload, and another user must view the announcement; execution is limited to that user’s Chamilo browser context.

CVSS severity4.8
Medium
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in Chamilo LMS 1.11.18 allows remote authenticated users to execute script in another user’s browser via system announcements. The vendor identifies the system-announcement editor as accepting administrator-inserted XSS content but does not publish the faulty file, function, or encoding operation. Administrator privileges are required to plant the payload, and another user must view the announcement; execution is limited to that user’s Chamilo browser context.

The record

CVE
CVE-2023-31799
Published
May 9, 2023
Updated
Jul 9, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 9, 2023CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
4.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo