Vulnerability Name:

CVE-2021-31829 (CCN-201175)

Assigned:2021-04-30
Published:2021-04-30
Updated:2022-01-01
Summary:kernel/bpf/verifier.c in the Linux kernel through 5.12.1 performs undesirable speculative loads, leading to disclosure of stack content via side-channel attacks, aka CID-801c6058d14a. The specific concern is not protecting the BPF stack area against speculative loads. Also, the BPF stack can contain uninitialized data that might represent sensitive information previously operated on by the kernel.
CVSS v3 Severity:5.5 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N)
4.8 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/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): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): None
Availibility (A): None
5.5 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N)
4.8 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:L/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): Low
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): None
Availibility (A): None
6.2 Medium (REDHAT CVSS v3.1 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)
5.4 Medium (REDHAT Temporal CVSS v3.1 Vector: CVSS:3.1/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
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-863
CWE-200
Vulnerability Consequences:Obtain Information
References:Source: MITRE
Type: CNA
CVE-2021-31829

Source: MISC
Type: Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/04/4

Source: XF
Type: UNKNOWN
linux-kernel-cve202131829-info-disc(201175)

Source: CCN
Type: Linux Kernel GIT Repository
bpf: Fix leakage of uninitialized bpf stack under speculation

Source: CCN
Type: Linux Kernel GIT Repository
bpf: Fix masking negation logic upon negative dst register

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/torvalds/linux/commit/801c6058d14a82179a7ee17a4b532cac6fad067f

Source: MLIST
Type: Mailing List, Third Party Advisory
[debian-lts-announce] 20210623 [SECURITY] [DLA 2690-1] linux-4.19 security update

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-5ad5249c43

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-9c0276e935

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-7c085ca697

Source: CCN
Type: oss-sec Mailing List, Tue, 4 May 2021 11:06:52 +0100
[CVE-2021-31829] Linux kernel protection of stack pointer against speculative pointer arithmetic can be bypassed to leak content of kernel memory

Vulnerable Configuration:Configuration 1:
  • cpe:/o:linux:linux_kernel:*:*:*:*:*:*:*:* (Version <= 5.12.1)

    • Configuration 2:
  • cpe:/o:fedoraproject:fedora:32:*:*:*:*:*:*:*
  • OR cpe:/o:fedoraproject:fedora:33:*:*:*:*:*:*:*
  • OR cpe:/o:fedoraproject:fedora:34:*:*:*:*:*:*:*

    • Configuration 3:
  • cpe:/o:debian:debian_linux:9.0:*:*:*:*:*:*:*

    • 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:*:*:*:*:*

    • * 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 *
    fedoraproject fedora 32
    fedoraproject fedora 33
    fedoraproject fedora 34
    debian debian linux 9.0