CVE-2024-5521 | Cross-Site Scripting stored in Alkacon OpenCMS

Two Cross-Site Scripting vulnerabilities have been discovered in Alkacon's OpenCMS affecting version 16, which could allow a user having the roles of gallery editor or VFS resource manager will have the permission to upload images in the .svg format containing JavaScript code. The code will be executed the moment another user accesses the image.

Published: 2024-05-30 Last update: 2025-04-10 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-5521 is rated Moderate Risk (41.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.23%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-5521

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-07-13 0.10% 0.23% +0.13%
2 2025-04-15 0.18% 0.10% -0.07%
3 2025-03-30 — 0.18% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-5521

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.1 2.7 [email protected]
6.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.1 2.7 [email protected]

Weakness enumeration for CVE-2024-5521

Affected software / configurations for CVE-2024-5521

Vendor Product Version Raw CPE
alkacon opencms 16.0.0 cpe:2.3:a:alkacon:opencms:16.0.0:*:*:*:*:*:*:*

References for CVE-2024-5521

cvelogic Threat Intelligence