CVE-2026-24400 Security Details

CVE ID

CVE-2026-24400

CWE

CWE-611

CVE Description

AssertJ provides Fluent testing assertions for Java and the Java Virtual Machine (JVM). Starting in version 1.4.0 and prior to version 3.27.7, an XML External Entity (XXE) vulnerability exists in `org.assertj.core.util.xml.XmlStringPrettyFormatter`: the `toXmlDocument(String)` method initializes `DocumentBuilderFactory` with default settings, without disabling DTDs or external entities. This formatter is used by the `isXmlEqualTo(CharSequence)` assertion for `CharSequence` values. An application is vulnerable only when it uses untrusted XML input with either `isXmlEqualTo(CharSequence)` from `org.assertj.core.api.AbstractCharSequenceAssert` or `xmlPrettyFormat(String)` from `org.assertj.core.util.xml.XmlStringPrettyFormatter`. If untrusted XML input is processed by tone of these methods, an attacker couldnread arbitrary local files via `file://` URIs (e.g., `/etc/passwd`, application configuration files); perform Server-Side Request Forgery (SSRF) via HTTP/HTTPS URIs, and/or cause Denial of Service via "Billion Laughs" entity expansion attacks. `isXmlEqualTo(CharSequence)` has been deprecated in favor of XMLUnit in version 3.18.0 and will be removed in version 4.0. Users of affected versions should, in order of preference: replace `isXmlEqualTo(CharSequence)` with XMLUnit, upgrade to version 3.27.7, or avoid using `isXmlEqualTo(CharSequence)` or `XmlStringPrettyFormatter` with untrusted input. `XmlStringPrettyFormatter` has historically been considered a utility for `isXmlEqualTo(CharSequence)` rather than a feature for AssertJ users, so it is deprecated in version 3.27.7 and removed in version 4.0, with no replacement.

Published

Jan 27, 2026

CVSS Score & Severity

9.1Critical

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

EPSS Score

0.029%

Malware

malware

KEV Status

Not in KEV Catalog: No known exploits

Vulnerable Methods

org/assertj/core/util/xml/XmlStringPrettyFormatter.toXmlDocument(Ljava/lang/String;)Lorg/w3c/dom/Document;

JVMVulnerable params: 0

Affected Ecosystems

affected

Source

National Vulnerability Database

References

GitHub · Advisory · GHSA-rqfh-9r24-8c9rTHIRD_PARTY