Integer overflow in Linux Kernel

CVE-2018-12896

An issue was discovered in the Linux kernel through 4.17.3. An Integer Overflow in kernel/time/posix-timers.c in the POSIX timer code is caused by the way the overrun accounting works. Depending on interval and expiry time values, the overrun can be larger than INT_MAX, but the accounting is int based. This basically makes the accounting values, which are visible to user space via timer_getoverrun(2) and siginfo::si_overrun, random. For example, a local user can cause a denial of service (signed integer overflow) via crafted mmap, futex, timer_create, and timer_settime system calls.

Vulnerability class: Integer Overflow

EPSS: 0.006 (47.0th 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:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

  • cve@mitre.org (x_refsource_MISC, Issue Tracking, Vendor 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 (Patch, Third Party Advisory, x_refsource_MISC)
  • 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 (x_refsource_UBUNTU, vendor-advisory, 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 (Exploit, Third Party Advisory, x_refsource_MISC)

Frequently asked questions

What is CVE-2018-12896?
CVE-2018-12896 is a medium-severity vulnerability in Linux Kernel, classified under Integer Overflow or Wraparound. CVSS score: 5.5/10. Published 2018-07-02.
How severe is CVE-2018-12896?
Medium severity. CVSS v3 base score is 5.5 out of 10.