QMarkdown Cross-Site Scripting (XSS) vulnerability

Description

QMarkdown (aka quasar-ui-qmarkdown) before 2.0.5 allows XSS via headers even when when no-html is set.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2025-04-20 21:30:25 UTC
Updated
2025-04-21 16:18:47 UTC
GitHub reviewed
2025-04-21 16:18:45 UTC
NVD published
2025-04-20

EPSS Score

Score Percentile
0.13% 32.47%

CVSS Scores

Base score Version Severity Vector
4.9 3.1
CVSS:3.1/AV:N/AC:H/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: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: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
npm @quasar/quasar-ui-qmarkdown < 2.0.5 2.0.5

References

cvelogic Threat Intelligence