CVE intelligence and bounded remediation

CVE-2018-6854 — Sophos Safeguard Easy Device Encryption Client security vulnerability

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 of this condition to modify the SEP_TOKEN_PRIVILEGES structure of the Token object belonging to the exploit process and grant SE_DEBUG_NAME privilege. This allows the exploit process to interact wit…

Severity

High

CVSS

7.8 (3.0)

Published

2018-07-09

CISA KEV

Not currently listed

Ecosystem

software/application

Weaknesses

CWE-119