Kernel: Cross-VM ASL INtrospection (CAIN)
Published Mar 3, 2017
3.3
LOWCVSS 3.1
EPSS 0.94%
Description
Kernel Samepage Merging (KSM) in the Linux kernel 2.6.32 through 4.x does not prevent use of a write-timing side channel, which allows guest OS users to defeat the ASLR protection mechanism on other guest OS instances via a Cross-VM ASL INtrospection (CAIN) attack. NOTE: the vendor states "Basically if you care about this attack vector, disable deduplication." Share-until-written approaches for memory conservation among mutually untrusting tenants are inherently detectable for information disclosure, and can be classified as potentially misunderstood behaviors rather than vulnerabilities
Affected products
No data.
Configuration 1
- ≥ 2.6.32 · ≤ 4.20.15
Configuration 2
- 4.0
- 5.0
- 6.0
- 7.0
No data.
Red Hat Enterprise Linux 4
kernel
Will not fix
Red Hat Enterprise Linux 5
kernel
Will not fix
Red Hat Enterprise Linux 6
kernel
Will not fix
Red Hat Enterprise Linux 7
kernel
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 4 | kernel | Will not fix | n/a |
| Red Hat Enterprise Linux 5 | kernel | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | kernel | Will not fix | n/a |
| Red Hat Enterprise Linux 7 | kernel | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue affects the versions of the Linux Kernel as shipped with Red Hat Enterprise Linux 4, 5, 6 and 7. Red Hat Product Security has rated this issue as having Low security impact. Additionally a workaround is available. A future update may address this issue. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
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 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 | 0.94% (0.00942) | 59.56th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.94% (0.00942) | 56.19th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.11% (0.00112) | 27.38th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.06% (0.00060) | 27.55th | v3 (v2023.03.01) |
| Jun 21, 2024 | 0.06% (0.00060) | 25.74th | v3 (v2023.03.01) |
| Mar 27, 2024 | 0.06% (0.00060) | 23.73th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.06% (0.00057) | 21.73th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.03% (0.01034) | 41.69th | v2 (v2022.01.01) |
| Sep 10, 2022 | 1.03% (0.01034) | 39.91th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.03% (0.01034) | 37.91th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.03% (0.01034) | 20.32th | v2 (v2022.01.01) |
References (10)
- http://www.antoniobarresi.com/files/cain_advisory.txt x_refsource_MISCTechnical DescriptionThird Party Advisory
- http://www.kb.cert.org/vuls/id/935424 third-party-advisoryx_refsource_CERT-VNThird Party AdvisoryUS Government Resource
- http://www.securityfocus.com/bid/76256 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2015-2877 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1252096 x_refsource_MISCIssue TrackingThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2015-2877
- https://www.cve.org/CVERecord?id=CVE-2015-2877
- https://www.kb.cert.org/vuls/id/BGAR-A2CNKG x_refsource_MISCThird Party AdvisoryUS Government Resource
- https://www.kb.cert.org/vuls/id/BLUU-9ZAHZH x_refsource_MISCThird Party AdvisoryUS Government Resource
- https://www.usenix.org/system/files/conference/woot15/woot15-paper-barresi.pdf x_refsource_MISCTechnical DescriptionThird Party Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.antoniobarresi.com/files/cain_advisory.txt | x_refsource_MISCTechnical DescriptionThird Party Advisory | |
| http://www.kb.cert.org/vuls/id/935424 | third-party-advisoryx_refsource_CERT-VNThird Party AdvisoryUS Government Resource | |
| http://www.securityfocus.com/bid/76256 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| https://access.redhat.com/security/cve/CVE-2015-2877 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1252096 | x_refsource_MISCIssue TrackingThird Party Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2015-2877 | ||
| https://www.cve.org/CVERecord?id=CVE-2015-2877 | ||
| https://www.kb.cert.org/vuls/id/BGAR-A2CNKG | x_refsource_MISCThird Party AdvisoryUS Government Resource | |
| https://www.kb.cert.org/vuls/id/BLUU-9ZAHZH | x_refsource_MISCThird Party AdvisoryUS Government Resource | |
| https://www.usenix.org/system/files/conference/woot15/woot15-paper-barresi.pdf | x_refsource_MISCTechnical DescriptionThird Party Advisory |
Change history (0)
No recorded changes yet.