Vulnerability Name:

CVE-2021-28691 (CCN-203193)

Assigned:2021-06-08
Published:2021-06-08
Updated:2022-04-06
Summary:Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.
CVSS v3 Severity:7.8 High (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
6.8 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/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): High
Integrity (I): High
Availibility (A): High
4.0 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
3.5 Low (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/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): None
Integrity (I): None
Availibility (A): Low
CVSS v2 Severity:4.6 Medium (CVSS v2 Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): Partial
2.1 Low (CCN CVSS v2 Vector: AV:L/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
Vulnerability Type:CWE-416
Vulnerability Consequences:Obtain Information
References:Source: MITRE
Type: CNA
CVE-2021-28691

Source: CCN
Type: Xen Security Advisory XSA-374
Guest triggered use-after-free in Linux xen-netback

Source: XF
Type: UNKNOWN
xen-cve202128691-dos(203193)

Source: GENTOO
Type: Third Party Advisory
GLSA-202107-30

Source: CONFIRM
Type: Third Party Advisory
https://security.netapp.com/advisory/ntap-20210805-0002/

Source: CCN
Type: WhiteSource Vulnerability Database
CVE-2021-28691

Source: MISC
Type: Third Party Advisory
https://xenbits.xenproject.org/xsa/advisory-374.txt

Vulnerable Configuration:Configuration 1:
  • cpe:/o:linux:linux_kernel:*:*:*:*:*:*:*:* (Version >= 5.5.0 and < 5.12.2)

    • Configuration 2:
  • cpe:/a:netapp:cloud_backup:-:*:*:*:*:*:*:*

    • Configuration 3:
  • cpe:/o:netapp:h410c_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h410c:-:*:*:*:*:*:*:*

    • Configuration 4:
  • cpe:/o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h300s:-:*:*:*:*:*:*:*

    • Configuration 5:
  • cpe:/o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h500s:-:*:*:*:*:*:*:*

    • Configuration 6:
  • cpe:/o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h700s:-:*:*:*:*:*:*:*

    • Configuration 7:
  • cpe:/o:netapp:h300e_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h300e:-:*:*:*:*:*:*:*

    • Configuration 8:
  • cpe:/o:netapp:h500e_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h500e:-:*:*:*:*:*:*:*

    • Configuration 9:
  • cpe:/o:netapp:h700e_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h700e:-:*:*:*:*:*:*:*

    • Configuration 10:
  • cpe:/o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
  • AND
  • cpe:/h:netapp:h410s:-:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    linux linux kernel *
    netapp cloud backup -
    netapp h410c firmware -
    netapp h410c -
    netapp h300s firmware -
    netapp h300s -
    netapp h500s firmware -
    netapp h500s -
    netapp h700s firmware -
    netapp h700s -
    netapp h300e firmware -
    netapp h300e -
    netapp h500e firmware -
    netapp h500e -
    netapp h700e firmware -
    netapp h700e -
    netapp h410s firmware -
    netapp h410s -