Linux Kernel up to 5.14.14 kcapi.c detach_capi_ctr array index

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.3$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 5.14.14 and classified as critical. Affected by this issue is the function detach_capi_ctr of the file drivers/isdn/capi/kcapi.c. The manipulation leads to array index. This vulnerability is uniquely identified as CVE-2021-43389. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.14.14 (Operating System). This issue affects the function detach_capi_ctr of the file drivers/isdn/capi/kcapi.c. The manipulation with an unknown input leads to a array index vulnerability. Using CWE to declare the problem leads to CWE-129. The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array. Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 11/05/2021. The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2021-43389 since 11/04/2021. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 239841 (TencentOS Server 4: kernel (TSSA-2024:0960)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.14.15 eliminates this vulnerability. The upgrade is hosted for download at cdn.kernel.org. Applying a patch 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.

The vulnerability is also documented in the vulnerability database at Tenable (239841). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

Exploitinginfo

Class: Array index
CWE: CWE-129 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 239841
Nessus Name: TencentOS Server 4: kernel (TSSA-2024:0960)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.14.15
Patch: git.kernel.org

Timelineinfo

11/04/2021 🔍
11/05/2021 +1 days 🔍
11/05/2021 +0 days 🔍
06/20/2025 +1322 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-43389 (🔍)
GCVE (CVE): GCVE-0-2021-43389
GCVE (VulDB): GCVE-100-186077

Entryinfo

Created: 11/05/2021 01:16
Updated: 06/20/2025 00:52
Changes: 11/05/2021 01:16 (45), 11/09/2021 20:12 (1), 06/20/2025 00:52 (16)
Complete: 🔍
Cache ID: 216::103

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

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to stay up to date on a daily basis?

Enable the mail alert feature now!