CVE-2023-40547

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.

References

https://cybersecurity.thisweekin.xyz/cybersecurity-weekly-issue-36-38e5ef312c74?gi=dc6cf6c283f3&source=rss------information_security-5

https://cybersecurity.thisweekin.xyz/cybersecurity-weekly-issue-36-38e5ef312c74?gi=361da4f8b016&source=rss------security-5

https://cybersecurity.thisweekin.xyz/cybersecurity-weekly-issue-36-38e5ef312c74?gi=343b621b1396&source=rss------information_security-5

https://www.zdnet.com/article/shim-vulnerability-exposes-most-linux-systems-to-attack/#ftag=RSSbaffb68

https://www.bleepingcomputer.com/news/security/critical-flaw-in-shim-bootloader-impacts-major-linux-distros/

https://securityaffairs.com/158792/hacking/critical-shim-bug-linux.html

https://securityaffairs.com/158792/hacking/critical-shim-bug-linux.html?web_view=true

https://eclypsium.com/blog/the-real-shim-shady-how-cve-2023-40547-impacts-most-linux-systems/

https://bugzilla.redhat.com/show_bug.cgi?id=2234589

https://access.redhat.com/security/cve/CVE-2023-40547

https://access.redhat.com/errata/RHSA-2024:2086

https://access.redhat.com/errata/RHSA-2024:1959

https://access.redhat.com/errata/RHSA-2024:1903

https://access.redhat.com/errata/RHSA-2024:1902

https://access.redhat.com/errata/RHSA-2024:1883

https://access.redhat.com/errata/RHSA-2024:1876

https://access.redhat.com/errata/RHSA-2024:1873

https://access.redhat.com/errata/RHSA-2024:1835

https://access.redhat.com/errata/RHSA-2024:1834

http://www.openwall.com/lists/oss-security/2024/01/26/1

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3