CVE-2024-28191 | Contao may have unencoded insert tags in the frontend

Contao is an open source content management system. Starting in version 4.0.0 and prior to version 4.13.40 and 5.3.4, it is possible to inject insert tags in frontend forms if the output is structured in a very specific way. Contao versions 4.13.40 and 5.3.4 have a patch for this issue. As a workaround, do not output user data from frontend forms next to each other, always separate them by at least one character.

Published: 2024-04-09 Last update: 2025-01-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2024-28191 is rated Low Risk (39.3/100): CVSS Low severity, with medium exploitation likelihood (EPSS 0.96%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2024-28191

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 2025-11-21 0.61% 0.96% +0.35%
2 2025-11-18 0.96% 0.61% -0.35%
3 2025-08-29 0.96%

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-28191

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.1 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
1.6 1.4 [email protected]
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/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:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
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.
2.8 2.5 [email protected]

Weakness enumeration for CVE-2024-28191

GitHub Security Advisory for CVE-2024-28191

GHSA-747v-52c4-8vj8 · Severity: low · Ecosystem: composer — Contao: Unencoded insert tags in the frontend

Affected software / configurations for CVE-2024-28191

Vendor Product Version Raw CPE
contao contao >= 4.0.0, < 4.13.40 cpe:2.3:a:contao:contao:*:*:*:*:*:*:*:*
contao contao >= 5.0.0, < 5.3.4 cpe:2.3:a:contao:contao:*:*:*:*:*:*:*:*

References for CVE-2024-28191

cvelogic Threat Intelligence