CVE-2023-5369

Before correction, the copy_file_range system call checked only for the CAP_READ and CAP_WRITE capabilities on the input and output file descriptors, respectively. Using an offset is logically equivalent to seeking, and the system call must additionally require the CAP_SEEK capability.

This incorrect privilege check enabled sandboxed processes with only read or write but no seek capability on a file descriptor to read data from or write data to an arbitrary location within the file corresponding to that file descriptor.

Weakness

The product attempts to drop privileges but does not check or incorrectly checks to see if the drop succeeded.

Affected Software

Potential Mitigations

• Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
• Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

References

• https://security.FreeBSD.org/advisories/FreeBSD-SA-23:13.capsicum.asc
• https://security.netapp.com/advisory/ntap-20231124-0009/