What is CVE-2016-9604?

CVE-2016-9604 is a medium-severity vulnerability in Kernel Security, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 4.4/10. Published 2018-07-11.

How severe is CVE-2016-9604?

Medium severity. CVSS v3 base score is 4.4 out of 10.

Is CVE-2016-9604 known to be exploited?

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

Vulnerability in Kernel Security

CVE-2016-9604

It was discovered in the Linux kernel before 4.11-rc8 that root can gain direct access to an internal keyring, such as '.dns_resolver' in RHEL-7 or '.builtin_trusted_keys' upstream, by joining it as its session keyring. This allows root to bypass module signature verification by adding a new public key of its own devising to the keyring.

Published 2018-07-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (17.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Kernel Security — versions kernel 4.11-rc8
Linux Kernel — versions 4.11

Weakness classification (CWE)

Public proof-of-concept exploits

ARPSyndicate/cvemon

References

git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/ (Patch, Vendor Advisory)
access.redhat.com/errata/RHSA-2017:2669 (vendor-advisory, Third Party Advisory)
bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
bugzilla.novell.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-9604.html (Third Party Advisory)
www.securityfocus.com/bid/102135 (VDB Entry, Third Party Advisory, vdb-entry)
access.redhat.com/errata/RHSA-2017:2077 (vendor-advisory, Third Party Advisory)
access.redhat.com/errata/RHSA-2017:1842 (vendor-advisory, Third Party Advisory)

Frequently asked questions

What is CVE-2016-9604?: CVE-2016-9604 is a medium-severity vulnerability in Kernel Security, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 4.4/10. Published 2018-07-11.
How severe is CVE-2016-9604?: Medium severity. CVSS v3 base score is 4.4 out of 10.
Is CVE-2016-9604 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.