VulnerabilityModified

CVE-2023-40547

A remote code execution vulnerability was found in Shim.

HIGH 8.3EPSS 5.42%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (5.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1: 8.3 HIGHCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS: 5.42% probability · 92th percentile
CISA KEV: Not listed
Weakness: CWE-787, CWE-346
Affected: redhat/shim · redhat/enterprise linux
Source: secalert@redhat.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.