ALAS2023-2026-1448


Amazon Linux 2023 Security Advisory: ALAS2023-2026-1448
Advisory Released Date: 2026-03-05
Advisory Updated Date: 2026-03-05
Severity: Medium

Issue Overview:

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. (CVE-2026-24400)


Affected Packages:

assertj-core


Issue Correction:
Run dnf update assertj-core --releasever 2023.10.20260302 or dnf update --advisory ALAS2023-2026-1448 --releasever 2023.10.20260302 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation

New Packages:
noarch:
    assertj-core-3.19.0-5.amzn2023.0.4.noarch
    assertj-core-javadoc-3.19.0-5.amzn2023.0.4.noarch

src:
    assertj-core-3.19.0-5.amzn2023.0.4.src