What is CVE-2023-26119?

CVE-2023-26119 is a critical-severity vulnerability in Htmlunit, classified under Code Injection. CVSS score: 9.8/10. Published 2023-04-03.

How severe is CVE-2023-26119?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2023-26119 known to be exploited?

6 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

RCE in Htmlunit

CVE-2023-26119

Versions of the package net.sourceforge.htmlunit:htmlunit from 0 and before 3.0.0 are vulnerable to Remote Code Execution (RCE) via XSTL, when browsing the attacker’s webpage.

Vulnerability class: RCE (Remote Code Execution)

Published 2023-04-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.025 (84.3th percentile), scored 2026-10-08.

Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000

Affected products

Htmlunit
Net.sourceforge.htmlunit:htmlunit — versions 0

Weakness classification (CWE)

CWE-94 — Code Injection

Public proof-of-concept exploits

References

security.snyk.io/vuln/SNYK-JAVA-NETSOURCEFORGEHTMLUNIT-3252500 (Third Party Advisory)
github.com/HtmlUnit/htmlunit/commit/641325bbc84702dc9800ec7037aec061ce21956b (Patch)
siebene.github.io/2022/12/30/HtmlUnit-RCE/ (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2023-26119?: CVE-2023-26119 is a critical-severity vulnerability in Htmlunit, classified under Code Injection. CVSS score: 9.8/10. Published 2023-04-03.
How severe is CVE-2023-26119?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2023-26119 known to be exploited?: 6 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.