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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.006 (48.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 48.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
- Linux Kernel
- Canonical Ubuntu Linux — versions 12.04, 14.04, 16.04
- Debian Linux — versions 8.0
Weakness classification (CWE)
References
- bugzilla.kernel.org/show_bug.cgi (Issue Tracking, Vendor Advisory)
- usn.ubuntu.com/3848-2/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3847-1/ (vendor-advisory, Third Party Advisory)
- github.com/torvalds/linux/commit/78c9c4dfbf8c04883941445a195276bb4bb92c76 (Patch, Third Party Advisory)
- usn.ubuntu.com/3847-2/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3849-1/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3849-2/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3848-1/ (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/3847-3/ (vendor-advisory, Third Party Advisory)
- github.com/lcytxw/bug_repro/tree/master/bug_200189 (Exploit, Third Party Advisory)
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.