AMD EPYC ASP Bootloader toctou

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in AMD EPYC. The impacted element is an unknown function of the component ASP Bootloader. The manipulation results in toctou. This vulnerability is known as CVE-2021-26356. No exploit is available.

Detailsinfo

A vulnerability classified as problematic has been found in AMD EPYC (affected version not known). Affected is some unknown functionality of the component ASP Bootloader. 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. CVE summarizes:

A TOCTOU in ASP bootloader may allow an attacker to tamper with the SPI ROM following data read to memory potentially resulting in S3 data corruption and information disclosure.

The weakness was published 05/09/2023. The advisory is available at amd.com. This vulnerability is traded as CVE-2021-26356 since 01/29/2021. The technical details are unknown and an exploit is not available.

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

Vendor

Name

License

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

NVD Base Score: 7.4
NVD Vector: 🔍

CNA Base Score: 7.4
CNA 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: No
Local: No
Remote: Yes

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

01/29/2021 🔍
05/09/2023 +829 days 🔍
05/09/2023 +0 days 🔍
01/28/2025 +630 days 🔍

Sourcesinfo

Advisory: amd.com
Status: Confirmed

CVE: CVE-2021-26356 (🔍)
GCVE (CVE): GCVE-0-2021-26356
GCVE (VulDB): GCVE-100-228510

Entryinfo

Created: 05/09/2023 23:39
Updated: 01/28/2025 17:25
Changes: 05/09/2023 23:39 (37), 06/01/2023 20:16 (11), 01/28/2025 17:25 (26)
Complete: 🔍
Cache ID: 216::103

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