USN-7901-1: CRaC JDK 21 vulnerabilities

Publication date

1 December 2025

Overview

Several security issues were fixed in CRaC JDK 21.


Packages

  • openjdk-21-crac - Open Source Java implementation with Coordinated Restore at Checkpoints

Details

Jinfeng Guo discovered that the Security component of CRaC JDK 21 did not
correctly handle certain representations of encoded strings. An
unauthenticated remote attacker could possibly use this issue to modify
files or leak sensitive information. (CVE-2025-53057)

Darius Bohni discovered that the JAXP component of CRaC JDK 21 was
vulnerable to a XML External Entity (XEE) attack. An unauthenticated remote
attacker could possibly use this issue to modify files or leak sensitive
information. (CVE-2025-53066)

Yakov Shafranovich discovered that the Libraries component of CRaC JDK 21
contained an issue where certain Strings built with StringBuilder returned
an incorrect result for String.equals() checks. An unauthenticated remote
attacker could possibly use this issue to update, insert, or delete
accessible data. (

Jinfeng Guo discovered that the Security component of CRaC JDK 21 did not
correctly handle certain representations of encoded strings. An
unauthenticated remote attacker could possibly use this issue to modify
files or leak sensitive information. (CVE-2025-53057)

Darius Bohni discovered that the JAXP component of CRaC JDK 21 was
vulnerable to a XML External Entity (XEE) attack. An unauthenticated remote
attacker could possibly use this issue to modify files or leak sensitive
information. (CVE-2025-53066)

Yakov Shafranovich discovered that the Libraries component of CRaC JDK 21
contained an issue where certain Strings built with StringBuilder returned
an incorrect result for String.equals() checks. An unauthenticated remote
attacker could possibly use this issue to update, insert, or delete
accessible data. (CVE-2025-61748)

In addition to security fixes, the updated packages contain bug fixes, new
features, and possibly incompatible changes.

Please see the following for more information:
https://openjdk.org/groups/vulnerability/advisories/2025-10-21


Update instructions

This update uses a new upstream release, which includes additional bug fixes. After a standard system update you need to restart Java applications to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:


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