kernel: net: improve sequence number generation
Published May 24, 2012
9.1
CRITICALCVSS 3.1
EPSS 5.03%
Description
The (1) IPv4 and (2) IPv6 implementations in the Linux kernel before 3.1 use a modified MD4 algorithm to generate sequence numbers and Fragment Identification values, which makes it easier for remote attackers to cause a denial of service (disrupted networking) or hijack network sessions by predicting these values and sending crafted packets.
Affected products
No data.
Configuration 1
- < 3.1
Configuration 2
- 4.0
Configuration 3
- ≥ 6.0.0 · ≤ 6.4.0
- ≥ 10.1.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.1.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 10.0.0 · ≤ 10.2.4
- ≥ 11.0.0 · ≤ 11.1.0
- ≥ 2.1.0 · ≤ 2.3.0
- 3.0.0
- ≥ 6.0.0 · ≤ 6.1.0
- 7.0.0
No data.
Red Hat Enterprise Linux 5
kernel-0:2.6.18-274.7.1.el5
Fixed · RHSA-2011:1386
Red Hat Enterprise Linux 5.6 EUS - Server Only
kernel-0:2.6.18-238.28.1.el5
Fixed · RHSA-2011:1419
Red Hat Enterprise Linux 6
kernel-0:2.6.32-131.21.1.el6
Fixed · RHSA-2011:1465
Red Hat Enterprise MRG 2
kernel-rt-0:2.6.33.9-rt31.79.el6rt
Fixed · RHSA-2012:0010
Red Hat Enterprise Linux 4
kernel
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | kernel-0:2.6.18-274.7.1.el5 | Fixed | RHSA-2011:1386 |
| Red Hat Enterprise Linux 5.6 EUS - Server Only | kernel-0:2.6.18-238.28.1.el5 | Fixed | RHSA-2011:1419 |
| Red Hat Enterprise Linux 6 | kernel-0:2.6.32-131.21.1.el6 | Fixed | RHSA-2011:1465 |
| Red Hat Enterprise MRG 2 | kernel-rt-0:2.6.33.9-rt31.79.el6rt | Fixed | RHSA-2012:0010 |
| Red Hat Enterprise Linux 4 | kernel | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue affects the Linux kernel as shipped with Red Hat Enterprise Linux 4, 5, 6, and Red Hat Enterprise MRG. It has been addressed in Red Hat Enterprise Linux 5, 6, and Red Hat Enterprise MRG via https://rhn.redhat.com/errata/RHSA-2011-1386.html, https://rhn.redhat.com/errata/RHSA-2011-1465.html, and https://rhn.redhat.com/errata/RHSA-2012-0010.html. 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.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:N/I:P/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 (17 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 5.03% (0.05028) | 92.00th | v5 (v2026.06.15) |
| Jun 15, 2026 | 5.69% (0.05689) | 91.98th | v5 (v2026.06.15) |
| Mar 27, 2026 | 4.32% (0.04324) | 88.85th | v4 (v2025.03.14) |
| Jan 9, 2026 | 6.16% (0.06158) | 90.53th | v4 (v2025.03.14) |
| Oct 29, 2025 | 1.72% (0.01721) | 81.75th | v4 (v2025.03.14) |
| Jul 13, 2025 | 3.06% (0.03063) | 86.15th | v4 (v2025.03.14) |
| Mar 30, 2025 | 6.11% (0.06109) | 89.84th | v4 (v2025.03.14) |
| Mar 29, 2025 | 13.41% (0.13410) | 90.30th | v4 (v2025.03.14) |
| Mar 17, 2025 | 6.11% (0.06109) | 90.08th | v4 (v2025.03.14) |
| Dec 12, 2024 | 1.57% (0.01568) | 87.76th | v3 (v2023.03.01) |
| May 9, 2024 | 1.57% (0.01568) | 87.19th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.57% (0.01568) | 85.19th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.97% (0.01974) | 78.97th | v2 (v2022.01.01) |
| Feb 13, 2023 | 1.97% (0.01974) | 78.46th | v2 (v2022.01.01) |
| Feb 3, 2023 | 6.58% (0.06576) | 91.09th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.97% (0.01974) | 77.12th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.97% (0.01974) | 56.20th | v2 (v2022.01.01) |
No CWE recorded.
References (12)
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=6e5714eaf77d79ae1c8b47e3e040ff5411b717ec x_refsource_CONFIRM
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=bc0b96b54a21246e377122d54569eef71cec535f x_refsource_CONFIRM
- http://marc.info/?l=bugtraq&m=139447903326211&w=2 vendor-advisoryx_refsource_HPMailing ListThird Party Advisory
- http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.1 x_refsource_CONFIRMMailing ListPatchVendor Advisory
- http://www.openwall.com/lists/oss-security/2011/08/23/2 mailing-listx_refsource_MLISTMailing ListPatchThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2011-3188 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=732658 x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory
- https://github.com/torvalds/linux/commit/6e5714eaf77d79ae1c8b47e3e040ff5411b717ec x_refsource_CONFIRMPatchThird Party Advisory
- https://github.com/torvalds/linux/commit/bc0b96b54a21246e377122d54569eef71cec535f x_refsource_CONFIRMPatchThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2011-3188
- https://support.f5.com/csp/article/K15301?utm_source=f5support&%3Butm_medium=RSS x_refsource_CONFIRM
- https://www.cve.org/CVERecord?id=CVE-2011-3188
Change history (0)
No recorded changes yet.