Linux Kernel up to 5.10.74/5.14.13 btrfs_replace_file_extents injection

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 5.10.74/5.14.13. This affects the function btrfs_replace_file_extents. Performing a manipulation results in injection. This vulnerability is known as CVE-2021-47433. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 5.10.74/5.14.13. This affects the function btrfs_replace_file_extents. The manipulation with an unknown input leads to a injection vulnerability. CWE is classifying the issue as CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. This is going to have an impact on integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix abort logic in btrfs_replace_file_extents Error injection testing uncovered a case where we'd end up with a corrupt file system with a missing extent in the middle of a file. This occurs because the if statement to decide if we should abort is wrong. The only way we would abort in this case is if we got a ret != -EOPNOTSUPP and we called from the file clone code. However the prealloc code uses this path too. Instead we need to abort if there is an error, and the only error we _don't_ abort on is -EOPNOTSUPP and only if we came from the clone file code.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47433 since 05/21/2024. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1055 for this issue.

Upgrading to version 5.10.75 or 5.14.14 eliminates this vulnerability. Applying the patch 0e32a2b85c7d/0e309e1152fc/4afb912f439c is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.9

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Injection
CWE: CWE-74 / CWE-707 / CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.10.75/5.14.14
Patch: 0e32a2b85c7d/0e309e1152fc/4afb912f439c

Timelineinfo

05/21/2024 🔍
05/22/2024 +1 days 🔍
05/22/2024 +0 days 🔍
09/25/2025 +491 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-47433 (🔍)
GCVE (CVE): GCVE-0-2021-47433
GCVE (VulDB): GCVE-100-265845

Entryinfo

Created: 05/22/2024 09:05
Updated: 09/25/2025 20:44
Changes: 05/22/2024 09:05 (56), 09/25/2025 20:44 (13)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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