What is CVE-2017-15126?

CVE-2017-15126 is a high-severity vulnerability in Linux Kernel, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.1/10. Published 2018-01-14.

How severe is CVE-2017-15126?

High severity. CVSS v3 base score is 8.1 out of 10.

Is CVE-2017-15126 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Linux Kernel

CVE-2017-15126

A use-after-free flaw was found in fs/userfaultfd.c in the Linux kernel before 4.13.6. The issue is related to the handling of fork failure when dealing with event messages. Failure to fork correctly can lead to a situation where a fork event will be removed from an already freed list of events with userfaultfd_ctx_put().

Vulnerability class: Buffer Overflow

Published 2018-01-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.041 (90.4th percentile), scored 2026-10-06.

Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 90.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.041 · newest: 0.041 · change: 0.000

Affected products

Linux Kernel
Linux Kernel Before 4.13.6 — versions Linux Kernel before 4.13.6

Weakness classification (CWE)

Public proof-of-concept exploits

References

www.securityfocus.com/bid/102516 (VDB Entry, Third Party Advisory, vdb-entry)
git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/ (Vendor Advisory)
bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
access.redhat.com/errata/RHSA-2018:1062 (vendor-advisory, Third Party Advisory)
github.com/torvalds/linux/commit/384632e67e0829deb8015ee6ad916b180049d252 (Third Party Advisory)
access.redhat.com/errata/RHSA-2018:0676 (vendor-advisory, Third Party Advisory)
www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.6 (Vendor Advisory)
access.redhat.com/security/cve/CVE-2017-15126 (Third Party Advisory)

Frequently asked questions

What is CVE-2017-15126?: CVE-2017-15126 is a high-severity vulnerability in Linux Kernel, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.1/10. Published 2018-01-14.
How severe is CVE-2017-15126?: High severity. CVSS v3 base score is 8.1 out of 10.
Is CVE-2017-15126 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.