5.5
MEDIUM
CVE-2021-47343
"Dm Thin Linux Kernel Uninitialized Pointer Assignment"
Description

In the Linux kernel, the following vulnerability has been resolved: dm btree remove: assign new_root only when removal succeeds remove_raw() in dm_btree_remove() may fail due to IO read error (e.g. read the content of origin block fails during shadowing), and the value of shadow_spine::root is uninitialized, but the uninitialized value is still assign to new_root in the end of dm_btree_remove(). For dm-thin, the value of pmd->details_root or pmd->root will become an uninitialized value, so if trying to read details_info tree again out-of-bound memory may occur as showed below: general protection fault, probably for non-canonical address 0x3fdcb14c8d7520 CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6 Hardware name: QEMU Standard PC RIP: 0010:metadata_ll_load_ie+0x14/0x30 Call Trace: sm_metadata_count_is_more_than_one+0xb9/0xe0 dm_tm_shadow_block+0x52/0x1c0 shadow_step+0x59/0xf0 remove_raw+0xb2/0x170 dm_btree_remove+0xf4/0x1c0 dm_pool_delete_thin_device+0xc3/0x140 pool_message+0x218/0x2b0 target_message+0x251/0x290 ctl_ioctl+0x1c4/0x4d0 dm_ctl_ioctl+0xe/0x20 __x64_sys_ioctl+0x7b/0xb0 do_syscall_64+0x40/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixing it by only assign new_root when removal succeeds

INFO

Published Date :

May 21, 2024, 3:15 p.m.

Last Modified :

May 12, 2025, 7:58 p.m.

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Remotely Exploitable :

No

Impact Score :

3.6

Exploitability Score :

1.8
Affected Products

The following products are affected by CVE-2021-47343 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-47343.

URL Resource
https://git.kernel.org/stable/c/4c84b3e0728ffe10d89c633694c35a02b5c477dc Patch
https://git.kernel.org/stable/c/73f27adaa73e3057a9ec464e33c4f54d34ea5de3 Patch
https://git.kernel.org/stable/c/89bf942314b78d454db92427201421b5dec132d9 Patch
https://git.kernel.org/stable/c/8fbae4a1bdb5b889490cdee929e68540151536e5 Patch
https://git.kernel.org/stable/c/964d57d1962d7e68f0f578f05d9ae4a104d74851 Patch
https://git.kernel.org/stable/c/ad365e9351ac2b450e7e79932ff6abf59342d91a Patch
https://git.kernel.org/stable/c/b6e58b5466b2959f83034bead2e2e1395cca8aeb Patch
https://git.kernel.org/stable/c/ba47e65a5de3e0e8270301a409fc63d3129fdb9e Patch
https://git.kernel.org/stable/c/c154775619186781aaf8a99333ac07437a1768d5 Patch
https://git.kernel.org/stable/c/4c84b3e0728ffe10d89c633694c35a02b5c477dc Patch
https://git.kernel.org/stable/c/73f27adaa73e3057a9ec464e33c4f54d34ea5de3 Patch
https://git.kernel.org/stable/c/89bf942314b78d454db92427201421b5dec132d9 Patch
https://git.kernel.org/stable/c/8fbae4a1bdb5b889490cdee929e68540151536e5 Patch
https://git.kernel.org/stable/c/964d57d1962d7e68f0f578f05d9ae4a104d74851 Patch
https://git.kernel.org/stable/c/ad365e9351ac2b450e7e79932ff6abf59342d91a Patch
https://git.kernel.org/stable/c/b6e58b5466b2959f83034bead2e2e1395cca8aeb Patch
https://git.kernel.org/stable/c/ba47e65a5de3e0e8270301a409fc63d3129fdb9e Patch
https://git.kernel.org/stable/c/c154775619186781aaf8a99333ac07437a1768d5 Patch

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-47343 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-47343 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    May. 12, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-1188
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.5 up to (excluding) 4.9.276 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.10 up to (excluding) 4.14.240 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.15 up to (excluding) 4.19.198 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.20 up to (excluding) 5.4.133 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.51 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.12.18 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions up to (excluding) 4.4.276 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.13 up to (excluding) 5.13.3
    Added Reference Type CVE: https://git.kernel.org/stable/c/4c84b3e0728ffe10d89c633694c35a02b5c477dc Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/4c84b3e0728ffe10d89c633694c35a02b5c477dc Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/73f27adaa73e3057a9ec464e33c4f54d34ea5de3 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/73f27adaa73e3057a9ec464e33c4f54d34ea5de3 Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/89bf942314b78d454db92427201421b5dec132d9 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/89bf942314b78d454db92427201421b5dec132d9 Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/8fbae4a1bdb5b889490cdee929e68540151536e5 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/8fbae4a1bdb5b889490cdee929e68540151536e5 Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/964d57d1962d7e68f0f578f05d9ae4a104d74851 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/964d57d1962d7e68f0f578f05d9ae4a104d74851 Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/ad365e9351ac2b450e7e79932ff6abf59342d91a Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/ad365e9351ac2b450e7e79932ff6abf59342d91a Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/b6e58b5466b2959f83034bead2e2e1395cca8aeb Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/b6e58b5466b2959f83034bead2e2e1395cca8aeb Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/ba47e65a5de3e0e8270301a409fc63d3129fdb9e Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/ba47e65a5de3e0e8270301a409fc63d3129fdb9e Types: Patch
    Added Reference Type CVE: https://git.kernel.org/stable/c/c154775619186781aaf8a99333ac07437a1768d5 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/c154775619186781aaf8a99333ac07437a1768d5 Types: Patch
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://git.kernel.org/stable/c/4c84b3e0728ffe10d89c633694c35a02b5c477dc
    Added Reference https://git.kernel.org/stable/c/73f27adaa73e3057a9ec464e33c4f54d34ea5de3
    Added Reference https://git.kernel.org/stable/c/89bf942314b78d454db92427201421b5dec132d9
    Added Reference https://git.kernel.org/stable/c/8fbae4a1bdb5b889490cdee929e68540151536e5
    Added Reference https://git.kernel.org/stable/c/964d57d1962d7e68f0f578f05d9ae4a104d74851
    Added Reference https://git.kernel.org/stable/c/ad365e9351ac2b450e7e79932ff6abf59342d91a
    Added Reference https://git.kernel.org/stable/c/b6e58b5466b2959f83034bead2e2e1395cca8aeb
    Added Reference https://git.kernel.org/stable/c/ba47e65a5de3e0e8270301a409fc63d3129fdb9e
    Added Reference https://git.kernel.org/stable/c/c154775619186781aaf8a99333ac07437a1768d5
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 28, 2024

    Action Type Old Value New Value
  • CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 21, 2024

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: dm btree remove: assign new_root only when removal succeeds remove_raw() in dm_btree_remove() may fail due to IO read error (e.g. read the content of origin block fails during shadowing), and the value of shadow_spine::root is uninitialized, but the uninitialized value is still assign to new_root in the end of dm_btree_remove(). For dm-thin, the value of pmd->details_root or pmd->root will become an uninitialized value, so if trying to read details_info tree again out-of-bound memory may occur as showed below: general protection fault, probably for non-canonical address 0x3fdcb14c8d7520 CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6 Hardware name: QEMU Standard PC RIP: 0010:metadata_ll_load_ie+0x14/0x30 Call Trace: sm_metadata_count_is_more_than_one+0xb9/0xe0 dm_tm_shadow_block+0x52/0x1c0 shadow_step+0x59/0xf0 remove_raw+0xb2/0x170 dm_btree_remove+0xf4/0x1c0 dm_pool_delete_thin_device+0xc3/0x140 pool_message+0x218/0x2b0 target_message+0x251/0x290 ctl_ioctl+0x1c4/0x4d0 dm_ctl_ioctl+0xe/0x20 __x64_sys_ioctl+0x7b/0xb0 do_syscall_64+0x40/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixing it by only assign new_root when removal succeeds
    Added Reference kernel.org https://git.kernel.org/stable/c/4c84b3e0728ffe10d89c633694c35a02b5c477dc [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/c154775619186781aaf8a99333ac07437a1768d5 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/73f27adaa73e3057a9ec464e33c4f54d34ea5de3 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/8fbae4a1bdb5b889490cdee929e68540151536e5 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/964d57d1962d7e68f0f578f05d9ae4a104d74851 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/ba47e65a5de3e0e8270301a409fc63d3129fdb9e [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/89bf942314b78d454db92427201421b5dec132d9 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/ad365e9351ac2b450e7e79932ff6abf59342d91a [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/b6e58b5466b2959f83034bead2e2e1395cca8aeb [No types assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-47343 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-47343 weaknesses.

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
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Scope
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Latest DB Update: May. 15, 2025 10:04