kernel: sysctl: restrict write access to dmesg_restrict
Published May 24, 2012
4.0
MEDIUMCVSS 2.0
EPSS 0.35%
Description
The sysrq_sysctl_handler function in kernel/sysctl.c in the Linux kernel before 2.6.39 does not require the CAP_SYS_ADMIN capability to modify the dmesg_restrict value, which allows local users to bypass intended access restrictions and read the kernel ring buffer by leveraging root privileges, as demonstrated by a root user in a Linux Containers (aka LXC) environment.
Affected products
No data.
- < 2.6.39
No data.
Red Hat Enterprise Linux 6
kernel-0:2.6.32-220.13.1.el6
Fixed · RHSA-2012:0481
Red Hat Enterprise Linux 4
kernel
Affected
Red Hat Enterprise Linux 5
kernel
Affected
Red Hat Enterprise MRG 2
realtime-kernel
Affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | kernel-0:2.6.32-220.13.1.el6 | Fixed | RHSA-2012:0481 |
| Red Hat Enterprise Linux 4 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 5 | kernel | Affected | n/a |
| Red Hat Enterprise MRG 2 | realtime-kernel | Affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat Enterprise Linux 4 is now in Production 3 of the maintenance life-cycle, https://access.redhat.com/support/policy/updates/errata/, therefore the fix for this issue is not currently planned to be included in the future updates. Future kernel updates in Red Hat Enterprise Linux 5, 6 and Red Hat Enterprise MRG may address this flaw.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:L/AC:H/Au:N/C:C/I:N/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 | 0.35% (0.00349) | 26.17th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.35% (0.00349) | 26.57th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.06% (0.00055) | 14.27th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.04% (0.00042) | 5.07th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00042) | 5.63th | v3 (v2023.03.01) |
| Mar 6, 2023 | 0.95% (0.00950) | 32.28th | v2 (v2022.01.01) |
| Feb 13, 2023 | 0.95% (0.00950) | 31.86th | v2 (v2022.01.01) |
| Feb 3, 2023 | 1.03% (0.01034) | 40.96th | v2 (v2022.01.01) |
| Sep 10, 2022 | 0.95% (0.00950) | 30.63th | v2 (v2022.01.01) |
| Apr 1, 2022 | 0.95% (0.00950) | 28.61th | v2 (v2022.01.01) |
| Feb 4, 2022 | 0.95% (0.00950) | 13.46th | v2 (v2022.01.01) |
References (8)
- http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39 x_refsource_CONFIRMBroken Link
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=bfdc0b497faa82a0ba2f9dddcf109231dd519fcc x_refsource_CONFIRM
- http://www.openwall.com/lists/oss-security/2011/10/26/10 mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2011-4080 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=749243 Issue Tracking
- https://github.com/torvalds/linux/commit/bfdc0b497faa82a0ba2f9dddcf109231dd519fcc x_refsource_CONFIRMPatchThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2011-4080
- https://www.cve.org/CVERecord?id=CVE-2011-4080
| Link | Providers | Tags |
|---|---|---|
| http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39 | x_refsource_CONFIRMBroken Link | |
| http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=bfdc0b497faa82a0ba2f9dddcf109231dd519fcc | x_refsource_CONFIRM | |
| http://www.openwall.com/lists/oss-security/2011/10/26/10 | mailing-listx_refsource_MLISTMailing ListThird Party Advisory | |
| https://access.redhat.com/security/cve/CVE-2011-4080 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=749243 | Issue Tracking | |
| https://github.com/torvalds/linux/commit/bfdc0b497faa82a0ba2f9dddcf109231dd519fcc | x_refsource_CONFIRMPatchThird Party Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2011-4080 | ||
| https://www.cve.org/CVERecord?id=CVE-2011-4080 |
Change history (0)
No recorded changes yet.