kernel: Race condition on CPU unplug leading to use-after-free
Published Nov 16, 2016
7.0
HIGHCVSS 3.1
EPSS 1.43%
Description
Race condition in kernel/events/core.c in the Linux kernel before 4.4 allows local users to gain privileges or cause a denial of service (use-after-free) by leveraging incorrect handling of an swevent data structure during a CPU unplug operation.
Affected products
No data.
- < 3.2.85
- ≥ 3.3 · < 3.16.40
- ≥ 3.17 · < 3.18.54
- ≥ 3.19 · < 4.4
No data.
Red Hat Enterprise Linux 5
kernel
Not affected
Red Hat Enterprise Linux 6
kernel
Affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-rt
Not affected
Red Hat Enterprise MRG 2
realtime-kernel
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise MRG 2 | realtime-kernel | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue affects the Linux kernel shipping with Red Hat Enterprise Linux 6. Future updates for the respective releases may address the issue. This issue does not not affect Red Hat Enterprise Linux 5, 7, MRG-2 kernels. This has been rated as having Moderate security impact and is not currently planned to be addressed in future updates of Red Hat Enterprise Linux 5. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
Red Hat mitigation
A possible mitigation is to only remove CPU's while the system is shut down. This will prevent local attackers from being able to abuse this flaw.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:H/Au:N/C:C/I:C/A:C
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Feb 5, 2024 · SSVC 2.0.3
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 (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.43% (0.01430) | 72.05th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.43% (0.01430) | 69.44th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.09% (0.00091) | 23.85th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.08% (0.00079) | 35.91th | v3 (v2023.03.01) |
| Dec 15, 2023 | 0.08% (0.00079) | 33.02th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.09% (0.00087) | 35.50th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Sep 10, 2022 | 1.02% (0.01018) | 38.88th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.02% (0.01018) | 36.86th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
References (8)
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=12ca6ad2e3a896256f086497a7c7406a547ee373 x_refsource_CONFIRMPatchThird Party AdvisoryVendor Advisory
- http://source.android.com/security/bulletin/2016-11-01.html x_refsource_CONFIRMThird Party Advisory
- http://www.securityfocus.com/bid/94207 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2015-8963 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1411245 Issue Tracking
- https://github.com/torvalds/linux/commit/12ca6ad2e3a896256f086497a7c7406a547ee373 x_refsource_CONFIRMPatchVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2015-8963
- https://www.cve.org/CVERecord?id=CVE-2015-8963
| Link | Providers | Tags |
|---|---|---|
| http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=12ca6ad2e3a896256f086497a7c7406a547ee373 | x_refsource_CONFIRMPatchThird Party AdvisoryVendor Advisory | |
| http://source.android.com/security/bulletin/2016-11-01.html | x_refsource_CONFIRMThird Party Advisory | |
| http://www.securityfocus.com/bid/94207 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| https://access.redhat.com/security/cve/CVE-2015-8963 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1411245 | Issue Tracking | |
| https://github.com/torvalds/linux/commit/12ca6ad2e3a896256f086497a7c7406a547ee373 | x_refsource_CONFIRMPatchVendor Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2015-8963 | ||
| https://www.cve.org/CVERecord?id=CVE-2015-8963 |
Change history (0)
No recorded changes yet.