Linux Kernel up to 5.13.2 smackfs smk_set_cipso privilege escalation

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.
6.5$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in Linux Kernel up to 5.13.2. This vulnerability affects the function smk_set_cipso of the component smackfs. Such manipulation leads to an unknown weakness. This vulnerability is documented as CVE-2021-47336. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 5.13.2. Affected by this issue is the function smk_set_cipso of the component smackfs. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: smackfs: restrict bytes count in smk_set_cipso() Oops, I failed to update subject line. From 07571157c91b98ce1a4aa70967531e64b78e8346 Mon Sep 17 00:00:00 2001 Date: Mon, 12 Apr 2021 22:25:06 +0900 Subject: [PATCH] smackfs: restrict bytes count in smk_set_cipso() Commit 7ef4c19d245f3dc2 ("smackfs: restrict bytes count in smackfs write functions") missed that count > SMK_CIPSOMAX check applies to only format == SMK_FIXED24_FMT case.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2021-47336 since 05/21/2024. Technical details are known, but there is no available exploit.

Upgrading to version 4.9.276, 4.14.240, 4.19.198, 5.4.133, 5.10.51, 5.12.18 or 5.13.3 eliminates this vulnerability. Applying the patch 5f9880403e6b/5c2dca9a7a7f/cbd87ba6a138/135122f174c3/3780348c1a0e/8f5c773a2871/258fd821f693/49ec114a6e62 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.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.5

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

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

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

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.9.276/4.14.240/4.19.198/5.4.133/5.10.51/5.12.18/5.13.3
Patch: 5f9880403e6b/5c2dca9a7a7f/cbd87ba6a138/135122f174c3/3780348c1a0e/8f5c773a2871/258fd821f693/49ec114a6e62

Timelineinfo

05/21/2024 🔍
05/21/2024 +0 days 🔍
05/21/2024 +0 days 🔍
05/13/2025 +357 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-47336 (🔍)
GCVE (CVE): GCVE-0-2021-47336
GCVE (VulDB): GCVE-100-265466

Entryinfo

Created: 05/21/2024 18:02
Updated: 05/13/2025 09:27
Changes: 05/21/2024 18:02 (56), 05/13/2025 09:27 (12)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

Want to know what is going to be exploited?

We predict KEV entries!