Kernel: Xen: Xsa-66: information leak through fbld instruction emulation
Published Oct 1, 2013
2.1
LOWCVSS 2.0
EPSS 0.40%
Description
The fbld instruction emulation in Xen 3.3.x through 4.3.x does not use the correct variable for the source effective address, which allows local HVM guests to obtain hypervisor stack information by reading the values used by the instruction.
Affected products
No data.
- 3.3.0
- 3.3.1
- 3.3.2
- 3.4.0
- 3.4.1
- 3.4.2
- 3.4.3
- 3.4.4
- 4.0.0
- 4.0.1
- 4.0.2
- 4.0.3
- 4.0.4
- 4.1.0
- 4.1.1
- 4.1.2
- 4.1.3
- 4.1.4
- 4.1.5
- 4.2.0
- 4.2.1
- 4.2.2
- 4.3.0
No data.
Red Hat Enterprise Linux 5
kernel-xen
Not affected
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise MRG 2
realtime-kernel
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | kernel-xen | Not affected | 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 MRG 2 | realtime-kernel | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect the versions of the kernel-xen package as shipped with Red Hat Enterprise Linux 5. This issue does not affect the versions of the Linux kernel package as shipped with Red Hat Enterprise Linux 6 and Red Hat Enterprise MRG as it does not have support for Xen hypervisor.
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:L/Au:N/C:P/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 2, 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 (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 0.40% (0.00395) | 31.39th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.40% (0.00395) | 31.10th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.11% (0.00110) | 26.34th | v4 (v2025.03.14) |
| Mar 29, 2025 | 1.16% (0.01158) | 65.64th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.11% (0.00110) | 26.98th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.06% (0.00060) | 27.61th | v3 (v2023.03.01) |
| May 31, 2024 | 0.06% (0.00060) | 25.45th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.06% (0.00060) | 23.45th | v3 (v2023.03.01) |
| Mar 6, 2023 | 0.95% (0.00950) | 32.28th | 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 (9)
- http://lists.opensuse.org/opensuse-security-announce/2014-03/msg00021.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-updates/2013-11/msg00009.html vendor-advisoryx_refsource_SUSE
- http://security.gentoo.org/glsa/glsa-201407-03.xml vendor-advisoryx_refsource_GENTOO
- http://www.debian.org/security/2014/dsa-3006 vendor-advisoryx_refsource_DEBIAN
- http://www.openwall.com/lists/oss-security/2013/09/30/3 mailing-listx_refsource_MLIST
- https://access.redhat.com/security/cve/CVE-2013-4361 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1009817 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2013-4361
- https://www.cve.org/CVERecord?id=CVE-2013-4361
| Link | Providers | Tags |
|---|---|---|
| http://lists.opensuse.org/opensuse-security-announce/2014-03/msg00021.html | vendor-advisoryx_refsource_SUSE | |
| http://lists.opensuse.org/opensuse-updates/2013-11/msg00009.html | vendor-advisoryx_refsource_SUSE | |
| http://security.gentoo.org/glsa/glsa-201407-03.xml | vendor-advisoryx_refsource_GENTOO | |
| http://www.debian.org/security/2014/dsa-3006 | vendor-advisoryx_refsource_DEBIAN | |
| http://www.openwall.com/lists/oss-security/2013/09/30/3 | mailing-listx_refsource_MLIST | |
| https://access.redhat.com/security/cve/CVE-2013-4361 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1009817 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2013-4361 | ||
| https://www.cve.org/CVERecord?id=CVE-2013-4361 |
Change history (0)
No recorded changes yet.