XSS/HTML Injection Vulnerability in Umbraco Backoffice Components

Description

Impact

Authenticated users are able to exploit an XSS vulnerability when viewing certain localized backoffice components.

Patches

Will be patched in 14.3.2 and 15.1.2.

Note:
This issue was reported by Pratik Patil from NetSPI @Nexusss-ppatil

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-01-21 19:59:13 UTC
Updated
2025-01-21 19:59:13 UTC
GitHub reviewed
2025-01-21 19:59:13 UTC
NVD published
2025-01-21

EPSS Score

Score Percentile
0.90% 75.51%

CVSS Scores

Base score Version Severity Vector
4.6 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.

Identifiers

CWEs

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

Credits

  • Nexusss-ppatil (reporter)

Affected packages (4)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
nuget Umbraco.Cms.StaticAssets >= 14.0.0, < 14.3.2 14.3.2
nuget Umbraco.Cms.StaticAssets >= 15.0.0, < 15.1.2 15.1.2
npm @umbraco-cms/backoffice >= 14.0.0, < 14.3.2 14.3.2
npm @umbraco-cms/backoffice >= 15.0.0, < 15.1.2 15.1.2

References

cvelogic Threat Intelligence