Linux Kernel up to 5.8.13 Secure Boot Forbidden Signature Database certs/blacklist.c privileges management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.5$5k-$25k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.8.13. This impacts an unknown function of the file certs/blacklist.c of the component Secure Boot Forbidden Signature Database. Such manipulation leads to privileges management. This vulnerability is listed as CVE-2020-26541. The attack must be carried out locally. There is no available exploit.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.8.13 (Operating System) and classified as critical. Affected by this issue is some unknown functionality of the file certs/blacklist.c of the component Secure Boot Forbidden Signature Database. The manipulation with an unknown input leads to a privileges management vulnerability. Using CWE to declare the problem leads to CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. Impacted is confidentiality, integrity, and availability. CVE summarizes:

The Linux kernel through 5.8.13 does not properly enforce the Secure Boot Forbidden Signature Database (aka dbx) protection mechanism. This affects certs/blacklist.c and certs/system_keyring.c.

The weakness was presented 10/02/2020. This vulnerability is handled as CVE-2020-26541 since 10/02/2020. The attack needs to be approached locally. Additional levels of successful authentication are necessary for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 11/15/2020). The MITRE ATT&CK project declares the attack technique as T1068.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

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Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

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

VulDB Base Score: 6.5
VulDB Temp Score: 6.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
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: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

10/02/2020 🔍
10/02/2020 +0 days 🔍
10/03/2020 +1 days 🔍
11/16/2020 +44 days 🔍

Sourcesinfo

Vendor: kernel.org

Status: Not defined

CVE: CVE-2020-26541 (🔍)
GCVE (CVE): GCVE-0-2020-26541
GCVE (VulDB): GCVE-100-162248

Entryinfo

Created: 10/03/2020 06:36
Updated: 11/16/2020 10:31
Changes: 10/03/2020 06:36 (37), 10/03/2020 06:41 (12), 11/15/2020 10:17 (1), 11/16/2020 10:31 (7)
Complete: 🔍
Cache ID: 216::103

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