Silverstipe CMS Stored XSS in custom meta tags

Description

A malicious content author could create a custom meta tag and execute an arbitrary JavaScript payload. This would require convincing a legitimate user to access a page and enter a custom keyboard shortcut.
This requires CMS access to exploit.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Not specified
Published (advisory)
2022-11-21 23:59:26 UTC
Updated
2023-09-20 10:18:39 UTC
GitHub reviewed
2022-11-21 23:59:26 UTC
NVD published
2022-11-22

EPSS Score

Score Percentile
0.32% 54.64%

CVSS Scores

Base score Version Severity Vector
5.4 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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.

Identifiers

CWEs

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

Affected packages (1)

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

Ecosystem Package Vulnerable range First patched Vulnerable functions
composer silverstripe/cms >= 4.0.0, < 4.11.3 4.11.3

References

cvelogic Threat Intelligence