kernel: security: The built-in keyrings for security tokens can be joined as a session and then modified by the root user
Published Jul 11, 2018
4.4
MEDIUMCVSS 3.0
EPSS 0.27%
Description
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.
Affected products
-
- Version kernel 4.11-rc8StatusaffectedConstraints-
- Version
- ≤ 4.11
- 4.11
- 4.11
- 4.11
- 4.11
- 4.11
- 4.11
- 4.11
No data.
Red Hat Enterprise Linux 7
kernel-0:3.10.0-693.el7
Fixed · RHSA-2017:1842
Red Hat Enterprise Linux 7
kernel-rt-0:3.10.0-693.rt56.617.el7
Fixed · RHSA-2017:2077
Red Hat Enterprise MRG 2
kernel-rt-1:3.10.0-693.2.1.rt56.585.el6rt
Fixed · RHSA-2017:2669
Red Hat Enterprise Linux 5
kernel
Not affected
Red Hat Enterprise Linux 6
kernel
Affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 7 | kernel-0:3.10.0-693.el7 | Fixed | RHSA-2017:1842 |
| Red Hat Enterprise Linux 7 | kernel-rt-0:3.10.0-693.rt56.617.el7 | Fixed | RHSA-2017:2077 |
| Red Hat Enterprise MRG 2 | kernel-rt-1:3.10.0-693.2.1.rt56.585.el6rt | Fixed | RHSA-2017:2669 |
| Red Hat Enterprise Linux 5 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 as the code with the flaw is not present in this product. This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 6, 7 and MRG-2. Future Linux kernel updates for the respective releases might address this issue.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
AV:L/AC:L/Au:N/C:N/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (11 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.27% (0.00271) | 17.47th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.26% (0.00261) | 17.18th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.03% (0.00026) | 4.45th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.06% (0.00062) | 28.23th | v3 (v2023.03.01) |
| Jun 14, 2024 | 0.06% (0.00062) | 26.36th | v3 (v2023.03.01) |
| Jul 5, 2023 | 0.06% (0.00062) | 24.31th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.05% (0.00049) | 15.37th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.10% (0.01104) | 54.09th | v2 (v2022.01.01) |
| Sep 17, 2022 | 1.10% (0.01104) | 52.45th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.10% (0.01104) | 50.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.10% (0.01104) | 28.85th | v2 (v2022.01.01) |
References (12)
- http://people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-9604.html x_refsource_CONFIRMThird Party Advisory
- http://www.securityfocus.com/bid/102135 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/errata/RHSA-2017:1842 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2017:2077 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2017:2669 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2016-9604 Vendor Advisory
- https://bugzilla.novell.com/show_bug.cgi?id=1035576 x_refsource_CONFIRMIssue TrackingThird Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1389433 Issue Tracking
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-9604 x_refsource_CONFIRMIssue TrackingThird Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ee8f844e3c5a73b999edf733df1c529d6503ec2f x_refsource_CONFIRMPatchVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2016-9604
- https://www.cve.org/CVERecord?id=CVE-2016-9604
Change history (0)
No recorded changes yet.