CVE-2021-26356

HighCVSS 7.4/10Last modified Jun 17, 2026

Description

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.

Metrics

CVSS 3.1 7.4/10CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
May 9, 2023
Last modified
Jun 17, 2026
NVD status
Modified

Related CVEs from 2021

CVE-2021-263607.8An attacker with local access to the system can make unauthorized modifications of the security configuration of the SOC registers. This couCVE-2021-263615.5A malicious or compromised User Application (UApp) or AGESA Boot Loader (ABL) could be used by an attacker to exfiltrate arbitrary memory frCVE-2021-263627.1A malicious or compromised UApp or ABL may be used by an attacker to issue a malformed system call which results in mapping sensitive SystemCVE-2021-263634.4A malicious or compromised UApp or ABL could potentially change the value that the ASP uses for its reserved DRAM, to one outside of the fenCVE-2021-263645.5Insufficient bounds checking in an SMU mailbox register could allow an attacker to potentially read outside of the SRAM address range which CVE-2021-263658.2Certain size values in firmware binary headers could trigger out of bounds reads during signature validation, leading to denial of service oCVE-2021-263667.1An attacker, who gained elevated privileges via some other vulnerability, may be able to read data from Boot ROM resulting in a loss of systCVE-2021-263676.0A malicious attacker in x86 can misconfigure the Trusted Memory Regions (TMRs), which may allow the attacker to set an arbitrary address ranCVE-2021-263684.4Insufficient check of the process type in Trusted OS (TOS) may allow an attacker with privileges to enable a lesser privileged process to unCVE-2021-263697.8A malicious or compromised UApp or ABL may be used by an attacker to send a malformed system call to the bootloader, resulting in out-of-bouCVE-2021-263707.1Improper validation of destination address in SVC_LOAD_FW_IMAGE_BY_INSTANCE and SVC_LOAD_BINARY_BY_ATTRIB in a malicious UApp or ABL may allCVE-2021-263715.5A compromised or malicious ABL or UApp could send a SHA256 system call to the bootloader, which may result in exposure of ASP memory to user
CVE-2021-26356: High severity, CVSS 7.4 | Vulnix