Vulnerability Name:

CVE-2021-20239 (CCN-195800)

Assigned:2020-12-17
Published:2021-01-29
Updated:2022-08-05
Summary:A flaw was found in the Linux kernel in versions before 5.4.92 in the BPF protocol. This flaw allows an attacker with a local account to leak information about kernel internal addresses. The highest threat from this vulnerability is to confidentiality.
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
6.5 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N)
5.7 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/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
3.8 Low (REDHAT CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N)
3.3 Low (REDHAT Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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): Changed
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
4.6 Medium (CCN CVSS v2 Vector: AV:L/AC:L/Au:S/C:C/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Local
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Complete
Integrity (I): None
Availibility (A): None
Vulnerability Type:CWE-119
CWE-200
Vulnerability Consequences:Obtain Information
References:Source: MITRE
Type: CNA
CVE-2021-20239

Source: CCN
Type: Red Hat Bugzilla - Bug 1923636
(CVE-2021-20239) - CVE-2021-20239 kernel: setsockopt System Call Untrusted Pointer Dereference Information Disclosure

Source: MISC
Type: Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1923636

Source: XF
Type: UNKNOWN
linux-kernel-setsockopt-info-disc(195800)

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

Source: CCN
Type: ZDI-21-100
Linux Kernel setsockopt System Call Untrusted Pointer Dereference Information Disclosure Vulnerability

Vulnerable Configuration:Configuration 1:
  • cpe:/o:linux:linux_kernel:*:*:*:*:*:*:*:* (Version < 5.4.92)

    • Configuration 2:
  • cpe:/o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux:5.0:*:*:*:*:*:*:*
  • OR cpe:/o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*

    • Configuration 3:
  • cpe:/o:fedoraproject:fedora:33:*:*:*:*:*:*:*

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

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

    • Configuration RedHat 3:
  • cpe:/a:redhat:enterprise_linux:8::realtime:*:*:*:*:*

    • Configuration RedHat 4:
  • cpe:/a:redhat:enterprise_linux:8::crb:*:*:*:*:*

    • Configuration RedHat 5:
  • cpe:/o:redhat:enterprise_linux:8:*:*:*:*:*:*:*

    • Configuration RedHat 6:
  • cpe:/o:redhat:enterprise_linux:8::baseos:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/o:linux:linux_kernel:5.4:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:com.redhat.rhsa:def:20214140
    P
    		RHSA-2021:4140: kernel-rt security and bug fix update (Moderate)
    2021-11-09
    oval:com.redhat.rhsa:def:20214356
    P
    		RHSA-2021:4356: kernel security, bug fix, and enhancement update (Moderate)
    2021-11-09
    BACK
    linux linux kernel *
    redhat enterprise linux 6.0
    redhat enterprise linux 5.0
    redhat enterprise linux 8.0
    fedoraproject fedora 33
    linux linux kernel 5.4