CVE Vulnerability

CVE-2018-6854

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 with higher privileged processes running as SYSTEM and execute code in their security context.

7.2 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 10

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

Scope

7.8 /10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://labs.nettitude.com/blog/cve-2018-6851-to-cve-2018-6857-sophos-privilege-escalation-vulnerabilities/ Exploit Technical Description
https://community.sophos.com/kb/en-us/131934 Patch Vendor Advisory
http://seclists.org/fulldisclosure/2018/Jul/20 Mailing List Third Party Advisory
Configurations

Configuration 1

cpe:2.3:a:sophos:safeguard_lan_crypt_client:3.95.1:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_lan_crypt_client:3.90.2:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_enterprise_client:8.00:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_enterprise_client:7.00:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_enterprise_client:6.10:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_enterprise_client:6.00:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_enterprise_client:6.00.1:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_easy_device_encryption_client:6.00:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_easy_device_encryption_client:6.10:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_easy_device_encryption_client:7.00:*:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_lan_crypt_client:3.95.1:ts:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_lan_crypt_client:3.90.1:ts:*:*:*:*:*:*
cpe:2.3:a:sophos:safeguard_enterprise_client:5.60.3:vs-nfd:*:*:*:*:*:*
Information

Published : 2018-07-09 06:29

Updated : 2019-10-03 12:03

NVD link : CVE-2018-6854

Mitre link : CVE-2018-6854

Products Affected
No products.
CWE
CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer