Vulnerability Name:

CVE-2015-2877 (CCN-106177)

Assigned:2015-08-05
Published:2015-08-05
Updated:2020-06-04
Summary:** DISPUTED ** 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.
CVSS v3 Severity:3.3 Low (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N)
2.9 Low (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): Low
Integrity (I): None
Availibility (A): None
4.0 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
3.5 Low (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): Low
Integrity (I): None
Availibility (A): None
CVSS v2 Severity:2.1 Low (CVSS v2 Vector: AV:L/AC:L/Au:N/C:P/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): None
2.1 Low (CCN CVSS v2 Vector: AV:L/AC:L/Au:N/C:P/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): None
Vulnerability Type:CWE-200
Vulnerability Consequences:Obtain Information
References:Source: MITRE
Type: CNA
CVE-2015-2877

Source: CCN
Type: Full Disclosure Mailing List, Wed, 05 Aug 2015 23:47:46 +0200
Security Advisory - "Cross-VM ASL INtrospection (CAIN)"

Source: MISC
Type: Technical Description, Third Party Advisory
http://www.antoniobarresi.com/files/cain_advisory.txt

Source: CCN
Type: US-CERT VU#935424
Virtual Machine Monitors (VMM) contain a memory deduplication vulnerability

Source: CERT-VN
Type: Third Party Advisory, US Government Resource
VU#935424

Source: CCN
Type: Linux Kernel Web site
The Linux Kernel Archives

Source: BID
Type: Third Party Advisory, VDB Entry
76256

Source: CCN
Type: BID-76256
Kernel Virtual Machine CVE-2015-2877 Memory Corruption Vulnerability

Source: CCN
Type: Red Hat Bugzilla – Bug 1252096
(CVE-2015-2877) CVE-2015-2877 Kernel: Cross-VM ASL INtrospection (CAIN)

Source: MISC
Type: Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1252096

Source: XF
Type: UNKNOWN
linux-kernel-cve20152877-info-disc(106177)

Source: MISC
Type: Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/BGAR-A2CNKG

Source: MISC
Type: Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/BLUU-9ZAHZH

Source: MISC
Type: Technical Description, Third Party Advisory
https://www.usenix.org/system/files/conference/woot15/woot15-paper-barresi.pdf

Vulnerable Configuration:Configuration 1:
  • cpe:/o:linux:linux_kernel:*:*:*:*:*:*:*:* (Version >= 2.6.32 and <= 4.20.15)

    • Configuration 2:
  • cpe:/o:redhat:enterprise_linux:4.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux:5.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/o:linux:linux_kernel:*:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:com.ubuntu.artful:def:20152877000
    V
    		CVE-2015-2877 on Ubuntu 17.10 (artful) - low.
    2017-03-03
    oval:com.ubuntu.xenial:def:20152877000
    V
    		CVE-2015-2877 on Ubuntu 16.04 LTS (xenial) - low.
    2017-03-03
    oval:com.ubuntu.bionic:def:20152877000
    V
    		CVE-2015-2877 on Ubuntu 18.04 LTS (bionic) - low.
    2017-03-03
    oval:com.ubuntu.precise:def:20152877000
    V
    		CVE-2015-2877 on Ubuntu 12.04 LTS (precise) - low.
    2017-03-03
    oval:com.ubuntu.trusty:def:20152877000
    V
    		CVE-2015-2877 on Ubuntu 14.04 LTS (trusty) - low.
    2017-03-03
    BACK
    linux linux kernel *
    redhat enterprise linux 4.0
    redhat enterprise linux 5.0
    redhat enterprise linux 6.0
    redhat enterprise linux 7.0
    linux linux kernel *