How severe is GHSA-x52f-h5g4-8qv5?

GHSA-x52f-h5g4-8qv5 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-x52f-h5g4-8qv5?

GHSA-x52f-h5g4-8qv5 affects the following packages: @marp-team/marp-core (npm), @marp-team/marp-core (npm). Ecosystems affected: npm.

How do I fix GHSA-x52f-h5g4-8qv5?

Update @marp-team/marp-core to 3.9.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-x52f-h5g4-8qv5 is resolved across your whole dependency graph.

How do I detect GHSA-x52f-h5g4-8qv5 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @marp-team/marp-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-x52f-h5g4-8qv5 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is GHSA-x52f-h5g4-8qv5 actively exploited in the wild?

No public exploit code has been indexed for GHSA-x52f-h5g4-8qv5 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-x52f-h5g4-8qv5?

GHSA-x52f-h5g4-8qv5 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 22th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-x52f-h5g4-8qv5?

GHSA-x52f-h5g4-8qv5 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-x52f-h5g4-8qv5 published, and has it been updated?

GHSA-x52f-h5g4-8qv5 was published on December 26, 2024 and was last updated on December 26, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

MEDIUM severity

GHSA-x52f-h5g4-8qv5 — @marp-team/marp-core

MEDIUMFix: marp-team/marp-core#282

GHSA-x52f-h5g4-8qv5 is a medium-severity (CVSS 5.3) Cross-site Scripting (XSS) vulnerability in @marp-team/marp-core. A fix is available for @marp-team/marp-core — see the affected versions and patch details below.

Marp Core allows XSS by improper neutralization of HTML sanitization

Also known asCVE-2024-56510

Published

Dec 26, 2024

Updated

Dec 26, 2024

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Sep 26, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-x52f-h5g4-8qv5.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs22th percentile — riskier than 22% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

GHSA-x52f-h5g4-8qv5 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

26other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

@marp-team/marp-corenpm

124Kdownloads / week

Description

Marp Core (@marp-team/marp-core) from v3.0.2 to v3.9.0 and v4.0.0, are vulnerable to cross-site scripting (XSS) due to improper neutralization of HTML sanitization.

Impact

Marp Core includes an HTML sanitizer with allowlist support. In the affected versions, the built-in allowlist is enabled by default. When the allowlist is active, if insufficient HTML comments are included, the sanitizer may fail to properly sanitize HTML content and lead cross-site scripting (XSS).

Patches

Marp Core v3.9.1 and v4.0.1 have been patched to fix that.

Workarounds

If you are unable to update the package immediately, disable all HTML tags by setting html: false option in the Marp class constructor.

const marp = new Marp({ html: false })

References

Credits

Thanks to @Ry0taK for finding out this vulnerability.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@marp-team/marp-core`	≥ 3.0.2&&< 3.9.1	3.9.1`npm install @marp-team/marp-core@3.9.1`
📦npm	`@marp-team/marp-core`	≥ 4.0.0&&< 4.0.1	4.0.1`npm install @marp-team/marp-core@4.0.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @marp-team/marp-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @marp-team/marp-core to 3.9.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-x52f-h5g4-8qv5 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

Marp Core ([`@marp-team/marp-core`](https://www.npmjs.com/package/@marp-team/marp-core)) from v3.0.2 to v3.9.0 and v4.0.0, are vulnerable to cross-site scripting (XSS) due to improper neutralization of HTML sanitization. ### Impact Marp Core includes an HTML sanitizer with allowlist support. In the affected versions, the built-in allowlist is enabled by default. When the allowlist is active, if insufficient HTML comments are included, the sanitizer may fail to properly sanitize HTML content and lead cross-site scripting (XSS). ### Patches Marp Core [v3.9.1](https://github.com/marp-team/ma