CVEvulnerability

CVE-2018-1000204

5.3 MEDIUM Published 2018-06-26 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2018-06-26
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.0 ([email protected])
5.3 MEDIUM — CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS 2.0 ([email protected])
6.3 MEDIUM — AV:N/AC:M/Au:S/C:C/I:N/A:N

Description

Linux Kernel version 3.18 to 4.16 incorrectly handles an SG_IO ioctl on /dev/sg0 with dxfer_direction=SG_DXFER_FROM_DEV and an empty 6-byte cmdp. This may lead to copying up to 1000 kernel heap pages to the userspace. This has been fixed upstream in https://github.com/torvalds/linux/commit/a45b599ad808c3c982fdcdc12b0b8611c2f92824 already. The problem has limited scope, as users don't usually have permissions to access SCSI devices. On the other hand, e.g. the Nero user manual suggests doing `chmod o+r+w /dev/sg*` to make the devices accessible. NOTE: third parties dispute the relevance of this report, noting that the requirement for an attacker to have both the CAP_SYS_ADMIN and CAP_SYS_RAWIO capabilities makes it "virtually impossible to exploit.

Affected configurations

• linux linux kernel (>= 3.18 <= 4.16) • canonical ubuntu linux 14.04 • canonical ubuntu linux 16.04 • canonical ubuntu linux 18.04 • debian debian linux 8.0

References