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Insertion of Sensitive Information into Log File

CVE-2019-19039

Severity Medium
Score 5.5/10

Summary

__btrfs_free_extent in fs/btrfs/extent-tree.c in the Linux kernel through 5.3.12 calls btrfs_print_leaf in a certain ENOENT case, which allows local users to obtain potentially sensitive information about register values via the dmesg program. NOTE: The BTRFS development team disputes this issues as not being a vulnerability because “1) The kernel provide facilities to restrict access to dmesg - dmesg_restrict=1 sysctl option. So it's really up to the system administrator to judge whether dmesg access shall be disallowed or not. 2) WARN/WARN_ON are widely used macros in the linux kernel. If this CVE is considered valid this would mean there are literally thousands CVE lurking in the kernel - something which clearly is not the case.

  • LOW
  • LOCAL
  • NONE
  • UNCHANGED
  • REQUIRED
  • NONE
  • HIGH
  • NONE

CWE-532 - Insertion of Sensitive Information into Log File

It's quite common for applications to save logs. For example, whenever a user requests a resource from a particular website, the web server writes information about the request to a log file. These files are helpful for identifying abnormal system activity, bugs, and evaluating the security controls of the application. Security of log files is critical for the overall security of the application and its confidential resources. An application that lacks appropriate logging levels can expose sensitive user data and system information stored on the log files to malicious users. This info can be exploited to compromise your system.

References

Advisory Timeline

  • Published