Vulnerability Name:

CVE-2017-12855

Assigned:2017-08-15
Published:2017-08-15
Updated:2017-11-14
Summary:Xen maintains the _GTF_{read,writ}ing bits as appropriate, to inform the guest that a grant is in use. A guest is expected not to modify the grant details while it is in use, whereas the guest is free to modify/reuse the grant entry when it is not in use. Under some circumstances, Xen will clear the status bits too early, incorrectly informing the guest that the grant is no longer in use. A guest may prematurely believe that a granted frame is safely private again, and reuse it in a way which contains sensitive information, while the domain on the far end of the grant is still using the grant. Xen 4.9, 4.8, 4.7, 4.6, and 4.5 are affected.
CVSS v3 Severity:6.5 Medium (CVSS v3 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N)
5.7 Medium (Temporal CVSS v3 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/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): Changed
Impact Metrics:Confidentiality (C): High
Integrity (I): None
Availibility (A): None
6.2 Medium (CCN CVSS v3 Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)
5.4 Medium (CCN Temporal CVSS v3 Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/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): High
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
References:Source: DEBIAN
Type: UNKNOWN
DSA-3969

Source: BID
Type: VENDOR_ADVISORY
100341

Source: SECTRACK
Type: VENDOR_ADVISORY
1039177

Source: CONFIRM
Type: VENDOR_ADVISORY
http://xenbits.xen.org/xsa/advisory-230.html

Source: XF
Type: UNKNOWN
xen-cve201712855-info-disc(130420)

Source: CONFIRM
Type: UNKNOWN
https://support.citrix.com/article/CTX225941

Vulnerable Configuration:Configuration 1:
  • cpe:/o:xen:xen:4.5.0:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.5.1:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.5.2:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.5.3:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.5.5:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.6.0:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.6.1:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.6.3:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.6.4:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.6.5:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.6.6:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.7.0:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.7.1:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.7.2:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.7.3:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.8.0:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.8.1:*:*:*:*:*:*:*
  • OR cpe:/o:xen:xen:4.9.0:*:*:*:*:*:*:*

  • Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:org.opensuse.security:def:201712855
    V
    CVE-2017-12855
    2017-11-19
    oval:com.ubuntu.xenial:def:201712855000
    V
    CVE-2017-12855 on Ubuntu 16.04 LTS (xenial) - medium.
    2017-08-15
    oval:com.ubuntu.trusty:def:201712855000
    V
    CVE-2017-12855 on Ubuntu 14.04 LTS (trusty) - medium.
    2017-08-15
    BACK
    xen xen 4.5.0
    xen xen 4.5.1
    xen xen 4.5.2
    xen xen 4.5.3
    xen xen 4.5.5
    xen xen 4.6.0
    xen xen 4.6.1
    xen xen 4.6.3
    xen xen 4.6.4
    xen xen 4.6.5
    xen xen 4.6.6
    xen xen 4.7.0
    xen xen 4.7.1
    xen xen 4.7.2
    xen xen 4.7.3
    xen xen 4.8.0
    xen xen 4.8.1
    xen xen 4.9.0