How severe is CVE-2024-21627?

CVE-2024-21627 has a CVSS score of 8.1/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2024-21627?

CVE-2024-21627 affects the following packages: prestashop/prestashop (Packagist), prestashop/prestashop (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2024-21627?

Update prestashop/prestashop to 8.1.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-21627 is resolved across your whole dependency graph.

How do I detect CVE-2024-21627 in my Packagist dependencies?

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

How do I mitigate CVE-2024-21627 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 CVE-2024-21627 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-21627 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 CVE-2024-21627?

CVE-2024-21627 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 45th 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 CVE-2024-21627?

CVE-2024-21627 is classified as Improper Input Validation (CWE-20), Cross-site Scripting (XSS) (CWE-79). These weakness types 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 CVE-2024-21627 published, and has it been updated?

CVE-2024-21627 was published on January 2, 2024 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘

🐘 Packagist

Not in CISA KEV

HIGH severity

CVE-2024-21627 — prestashop

HIGHFix: PrestaShop/PrestaShop@73cfb44

CVE-2024-21627 is a high-severity (CVSS 8.1) Improper Input Validation vulnerability in prestashop/prestashop. A fix is available for prestashop/prestashop — see the affected versions and patch details below.

Some attribute not escaped in Validate::isCleanHTML method

Also known asGHSA-xgpm-q3mq-46rq

Published

Jan 2, 2024

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
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 CVE-2024-21627.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs45th percentile — riskier than 45% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

2 pkgs affected

🐘prestashop/prestashop🐘prestashop/prestashop

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Some event attributes are not detected by the isCleanHTML method

Impact

Some modules using the isCleanHTML method could be vulnerable to xss

Patches

8.1.3, 1.7.8.11

Workarounds

The best workaround is to use the HTMLPurifier library to sanitize html input coming from users. The library is already available as a dependency in the PrestaShop project. Beware though that in legacy object models, fields of HTML type will call isCleanHTML.

Reporters

Reported by Antonio Russo (@Antonio-R1 on GitHub) and Antonio Rocco Spataro (@antoniospataro on GitHub).

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`prestashop/prestashop`	≥ 8.0.0-beta.1&&< 8.1.3	8.1.3`composer require prestashop/prestashop:^8.1.3`
🐘Packagist	`prestashop/prestashop`	all versions	1.7.8.11`composer require prestashop/prestashop:^1.7.8.11`

Affected Products

1 product · 2 configurations

Application

prestashopprestashop

≥ 8.0.0 && < 8.1.3

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for prestashop/prestashop, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update prestashop/prestashop to 8.1.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-21627 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

### Description Some event attributes are not detected by the isCleanHTML method ### Impact Some modules using the isCleanHTML method could be vulnerable to xss ### Patches 8.1.3, 1.7.8.11 ### Workarounds The best workaround is to use the `HTMLPurifier` library to sanitize html input coming from users. The library is already available as a dependency in the PrestaShop project. Beware though that in legacy object models, fields of `HTML` type will call `isCleanHTML`. ### Reporters Reported by Antonio Russo (@Antonio-R1 on GitHub) and Antonio Rocco Spataro (@antoniospataro on GitHub).