Out-of-bounds Read in Linux Kernel

CVE-2017-18344

The timer_create syscall implementation in kernel/time/posix-timers.c in the Linux kernel before 4.14.8 doesn't properly validate the sigevent->sigev_notify field, which leads to out-of-bounds access in the show_timer function (called when /proc/$PID/timers is read). This allows userspace applications to read arbitrary kernel memory (on a kernel built with CONFIG_POSIX_TIMERS and CONFIG_CHECKPOINT_RESTORE).

Vulnerability class: Buffer Overflow

EPSS: 0.032 (86.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_SECTRACK)
  • cve@mitre.org (Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)

Frequently asked questions

What is CVE-2017-18344?
CVE-2017-18344 is a medium-severity vulnerability in Linux Kernel, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2018-07-26.
How severe is CVE-2017-18344?
Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2017-18344 known to be exploited?
24 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.