CVE-2018-6854

/// Technical description

Sophos SafeGuard Enterprise before 8.00.5, SafeGuard Easy before 7.00.3, and SafeGuard LAN Crypt before 3.95.2 are vulnerable to Local Privilege Escalation via multiple IOCTLs, e.g., 0x8810200B, 0x8810200F, 0x8810201B, 0x8810201F, 0x8810202B, 0x8810202F, 0x8810203F, 0x8810204B, 0x88102003, 0x88102007, 0x88102013, 0x88102017, 0x88102027, 0x88102033, 0x88102037, 0x88102043, and 0x88102047. When some conditions in the user-controlled input buffer are not met, the driver writes an error code (0x2000001A) to a user-controlled address. Also, note that all the aforementioned IOCTLs use transfer type METHOD_NEITHER, which means that the I/O manager does not validate any of the supplied pointers and buffer sizes. So, even though the driver checks for input/output buffer sizes, it doesn't validate if the pointers to those buffers are actually valid. So, we can supply a pointer for the output buffer to a kernel address space address, and the error code will be written there. We can take advantage

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References