Vulnerability in Linux Kernel

CVE-2018-1000204

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.

EPSS: 0.019 (77.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

References

  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Third Party Advisory)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Third Party Advisory)
  • cve@mitre.org (Mailing List, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Third Party Advisory)
  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_CONFIRM, Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2018-1000204?
CVE-2018-1000204 is a medium-severity vulnerability in Linux Kernel. CVSS score: 5.3/10. Published 2018-06-26.
How severe is CVE-2018-1000204?
Medium severity. CVSS v3 base score is 5.3 out of 10.