kernel: mbcache code subject to softlockup DOS in cache management
Published Oct 16, 2016
5.5
MEDIUMCVSS 3.0
EPSS 0.45%
Description
The mbcache feature in the ext2 and ext4 filesystem implementations in the Linux kernel before 4.6 mishandles xattr block caching, which allows local users to cause a denial of service (soft lockup) via filesystem operations in environments that use many attributes, as demonstrated by Ceph and Samba.
Affected products
No data.
- ≤ 4.5.7
No data.
Red Hat Enterprise Linux 5
kernel
Will not fix
Red Hat Enterprise Linux 6
kernel
Not 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 | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not 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 does not affect any shiping version of Red Hat Enterprise Linux.
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:L/UI:N/S:U/C:N/I:N/A:H
AV:L/AC:L/Au:N/C:N/I:N/A:P
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 (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.45% (0.00454) | 37.09th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.45% (0.00454) | 35.81th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.07% (0.00067) | 17.91th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.04% (0.00044) | 11.89th | v3 (v2023.03.01) |
| Jul 2, 2024 | 0.04% (0.00044) | 10.25th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00044) | 8.24th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.55% (0.01547) | 74.98th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.55% (0.01547) | 74.94th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.55% (0.01547) | 72.92th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.55% (0.01547) | 51.82th | v2 (v2022.01.01) |
References (16)
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=82939d7999dfc1f1998c4b1c12e2f19edbdff272 x_refsource_CONFIRMPatch
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=be0726d33cb8f411945884664924bed3cb8c70ee x_refsource_CONFIRMPatch
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f9a61eb4e2471c56a63cd804c7474128138c38ac x_refsource_CONFIRMPatch
- http://www.openwall.com/lists/oss-security/2016/08/22/2 mailing-listx_refsource_MLISTThird Party Advisory
- http://www.openwall.com/lists/oss-security/2016/08/25/4 mailing-listx_refsource_MLISTPatchThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2015-8952 Vendor Advisory
- https://bugzilla.kernel.org/show_bug.cgi?id=107301 x_refsource_CONFIRMIssue TrackingThird Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1360968 x_refsource_CONFIRMIssue TrackingThird Party AdvisoryVDB Entry
- https://github.com/torvalds/linux/commit/82939d7999dfc1f1998c4b1c12e2f19edbdff272 x_refsource_CONFIRMVendor Advisory
- https://github.com/torvalds/linux/commit/be0726d33cb8f411945884664924bed3cb8c70ee x_refsource_CONFIRMIssue TrackingPatch
- https://github.com/torvalds/linux/commit/f9a61eb4e2471c56a63cd804c7474128138c38ac x_refsource_CONFIRMIssue Tracking
- https://lwn.net/Articles/668718/ x_refsource_CONFIRMThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2015-8952
- https://usn.ubuntu.com/3582-1/ vendor-advisoryx_refsource_UBUNTU
- https://usn.ubuntu.com/3582-2/ vendor-advisoryx_refsource_UBUNTU
- https://www.cve.org/CVERecord?id=CVE-2015-8952
Change history (0)
No recorded changes yet.