CVE-2026-21933
openjdk: Improve HttpServer Request handling (Oracle CPU 2026-01)
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · January 21, 2026
Updated · November 2, 2026
Description
Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: Networking). Supported versions that are affected are Oracle Java SE: 8u471, 8u471-b50, 8u471-perf, 11.0.29, 17.0.17, 21.0.9, 25.0.1; Oracle GraalVM for JDK: 17.0.17 and 21.0.9; Oracle GraalVM Enterprise Edition: 21.3.16. Easily exploitable vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition. Successful attacks require human interaction from a person other than the attacker and while the vulnerability is in Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition accessible data as well as unauthorized read access to a subset of Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition accessible data. Note: This vulnerability can be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs. This vulnerability also applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. CVSS 3.1 Base Score 6.1 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N).
Statement
This vulnerability is rated as Moderate impact because exploiting it requires an application to actively implement OpenJDK's built-in HTTP server to handle untrusted input, and successful exploitation necessitates user interaction to trigger response manipulation or cross-site scripting rather than enabling direct remote code execution. In typical Red Hat Enterprise Linux deployments, enterprise applications rely on standalone web servers or robust servlet containers rather than the lightweight embedded HTTP server provided by the JDK. Systems are only exposed if custom or third-party Java services directly expose this internal server component to untrusted network traffic.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE-93 · Improper Neutralization of CRLF Sequences