CVE-2021-21290— Netty 安全漏洞

Local Information Disclosure Vulnerability in Netty on Unix-Like systems due temporary files

Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty before version 4.1.59.Final there is a vulnerability on Unix-like systems involving an insecure temp file. When netty's multipart decoders are used local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk is enabled. On unix-like systems, the temporary directory is shared between all user. As such, writing to this directory using APIs that do not explicitly set the file/directory permissions can lead to information disclosure. Of note, this does not impact modern MacOS Operating Systems. The method "File.createTempFile" on unix-like systems creates a random file, but, by default will create this file with the permissions "-rw-r--r--". Thus, if sensitive information is written to this file, other local users can read this information. This is the case in netty's "AbstractDiskHttpData" is vulnerable. This has been fixed in version 4.1.59.Final. As a workaround, one may specify your own "java.io.tmpdir" when you start the JVM or use "DefaultHttpDataFactory.setBaseDir(...)" to set the directory to something that is only readable by the current user.

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

创建拥有不安全权限的临时文件

Netty 安全漏洞

Netty是Netty社区的一款非阻塞I/O客户端-服务器框架，它主要用于开发Java网络应用程序，如协议服务器和客户端等。 Netty 4.1.59之前版本存在安全漏洞，该漏洞源于当netty的多部分解码器被使用时，如果磁盘上的临时存储被启用，则本地信息可以通过本地系统临时目录进行公开。在类unix系统中，所有用户共享临时目录。因此，使用没有显式设置文件/目录权限的api写入该目录可能导致信息泄露。值得注意的是，这并不影响现代的MacOS操作系统。法”文件。createTempFile"在类unix系统

N/A

N/A