AMD CPU BIOS toctou

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.6$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in AMD CPU. Affected by this issue is some unknown functionality of the component BIOS. Performing a manipulation results in toctou. This vulnerability is reported as CVE-2021-46795. No exploit exists.

Detailsinfo

A vulnerability was found in AMD CPU (Chip Software) (the affected version is unknown). It has been classified as problematic. This affects an unknown code of the component BIOS. The manipulation with an unknown input leads to a toctou vulnerability. CWE is classifying the issue as CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A TOCTOU (time-of-check to time-of-use) vulnerability exists where an attacker may use a compromised BIOS to cause the TEE OS to read memory out of bounds that could potentially result in a denial of service.

The weakness was disclosed 01/11/2023. The advisory is shared at amd.com. This vulnerability is uniquely identified as CVE-2021-46795 since 05/04/2022. Neither technical details nor an exploit are publicly available.

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

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.6

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

NVD Base Score: 4.7
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Toctou
CWE: CWE-367 / CWE-362
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

05/04/2022 🔍
01/11/2023 +252 days 🔍
01/11/2023 +0 days 🔍
04/09/2025 +819 days 🔍

Sourcesinfo

Advisory: amd.com
Status: Confirmed

CVE: CVE-2021-46795 (🔍)
GCVE (CVE): GCVE-0-2021-46795
GCVE (VulDB): GCVE-100-217977

Entryinfo

Created: 01/11/2023 14:45
Updated: 04/09/2025 21:17
Changes: 01/11/2023 14:45 (38), 02/01/2023 14:23 (9), 04/09/2025 21:17 (16)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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