What is CVE-2023-4241?

CVE-2023-4241 is a high-severity vulnerability in Cloudflare Lol-Html, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2023-08-16.

How severe is CVE-2023-4241?

High severity. CVSS v3 base score is 7.5 out of 10.

Improper input validation in Cloudflare Lol-Html

CVE-2023-4241

lol-html can cause panics on certain HTML inputs. Anyone processing arbitrary 3rd party HTML with the library is affected.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2023-08-16 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.007 (50.8th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Cloudflare Lol-Html — versions 0

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

github.com/cloudflare/lol-html/security/advisories/GHSA-c3x7-354f-4p2x (Vendor Advisory)

Frequently asked questions

What is CVE-2023-4241?: CVE-2023-4241 is a high-severity vulnerability in Cloudflare Lol-Html, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2023-08-16.
How severe is CVE-2023-4241?: High severity. CVSS v3 base score is 7.5 out of 10.