A flaw was found in the SFTP backend in gvfs. When mounting a share and reading a file, a malicious SFTP server can cause read_reply() to process a length that exceeds the size requested by the client. The function does not verify the server-provided length against the allocated buffer size, causing the operation to write past the intended boundaries.
This issue allows a malicious server to corrupt adjacent heap memory in the gvfsd-sftp process, resulting in a denial of service as the process aborts upon detecting the heap corruption or potentially allowing arbitrary code execution.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1