Vulnerability Name:

CVE-2021-3543 (CCN-202837)

Assigned:2021-04-29
Published:2021-04-29
Updated:2022-06-03
Summary:A flaw null pointer dereference in the Nitro Enclaves kernel driver was found in the way that Enclaves VMs forces closures on the enclave file descriptor. A local user of a host machine could use this flaw to crash the system or escalate their privileges on the system.
CVSS v3 Severity:6.7 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H)
5.8 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/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): High
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
6.7 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H)
5.8 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/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): High
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
6.7 Medium (REDHAT CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H)
5.8 Medium (REDHAT Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:H/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): High
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
CVSS v2 Severity:7.2 High (CVSS v2 Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Complete
Integrity (I): Complete
Availibility (A): Complete
6.8 Medium (CCN CVSS v2 Vector: AV:L/AC:L/Au:S/C:C/I:C/A:C)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Complete
Integrity (I): Complete
Availibility (A): Complete
Vulnerability Type:CWE-476
CWE-416
CWE-476
CWE-416
Vulnerability Consequences:Gain Privileges
References:Source: MITRE
Type: CNA
CVE-2021-3543

Source: CCN
Type: Red Hat Bugzilla – Bug 1953022
(CVE-2021-3543) - CVE-2021-3543 kernel: nitro_enclaves stale file descriptors on failed usercopy

Source: MISC
Type: Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1953022

Source: XF
Type: UNKNOWN
amazon-nitro-cve20213543-priv-esc(202837)

Source: CCN
Type: Kernel GIT Repository
[PATCH v1 0/1] Nitro Enclaves kernel driver issue fix

Source: MISC
Type: Patch, Vendor Advisory
https://lore.kernel.org/lkml/20210429165941.27020-2-andraprs@amazon.com/

Vulnerable Configuration:Configuration 1:
  • cpe:/a:nitro_enclaves_project:nitro_enclaves:*:*:*:*:*:*:*:* (Version < 5.10.0)

    • Configuration 2:
  • cpe:/o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*

    • Configuration 3:
  • cpe:/o:fedoraproject:fedora:34:*:*:*:*:*:*:*

    • Configuration RedHat 1:
  • cpe:/a:redhat:enterprise_linux:8:*:*:*:*:*:*:*

    • Configuration RedHat 2:
  • cpe:/a:redhat:enterprise_linux:8::crb:*:*:*:*:*

    • Configuration RedHat 3:
  • cpe:/o:redhat:enterprise_linux:8:*:*:*:*:*:*:*

    • Configuration RedHat 4:
  • cpe:/o:redhat:enterprise_linux:8::baseos:*:*:*:*:*

    • Configuration RedHat 5:
  • cpe:/a:redhat:enterprise_linux:8::nfv:*:*:*:*:*

    • Configuration RedHat 6:
  • cpe:/a:redhat:enterprise_linux:8::realtime:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:com.redhat.rhsa:def:20212168
    P
    		RHSA-2021:2168: kernel security and bug fix update (Important)
    2021-06-01
    oval:com.redhat.rhsa:def:20212169
    P
    		RHSA-2021:2169: kernel-rt security and bug fix update (Important)
    2021-06-01
    BACK
    nitro_enclaves_project nitro enclaves *
    redhat enterprise linux 8.0
    fedoraproject fedora 34