Shim: rce in http boot support may lead to secure boot bypass

8.3 CVSS

Vulnerability Description

A remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP request, leading to a completely controlled out-of-bounds write primitive and complete system compromise. This flaw is only exploitable during the early boot phase, an attacker needs to perform a Man-in-the-Middle or compromise the boot server to be able to exploit this vulnerability successfully.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

Red Hat would like to thank Bill Demirkapi (Microsoft Security Response Center) for reporting this issue.

References

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Affected Vendor

Red Hat

View all reports →

Affected Software

Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 8.2 Advanced Update Support, Red Hat Enterprise Linux 8.2 Telecommunications Update Service, Red Hat Enterprise Linux 8.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Telecommunications Update Service, Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions, Red Hat Enterprise Linux 8.6 Extended Update Support, Red Hat Enterprise Linux 8.8 Extended Update Support, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.0 Extended Update Support, Red Hat Enterprise Linux 9.2 Extended Update Support

Vulnerable Versions:

0:15.8-3.el7, 0:15.8-1.el7, 0:15.8-4.el8_9, 0:15.8-2.el8_2, 0:15.8-2.el8_4, 0:15.8-2.el8_6, 0:15.8-2.el8, 0:15.8-4.el9_3, 0:15.8-3.el9, 0:15.8-2.el9, 0:15.8-3.el9_2