Vulnerability identifier: #VU86241

Vulnerability risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-40546

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Shim
Universal components / Libraries / Libraries used by multiple products

Vendor: Red Hat Bootloader Team

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error within the mirror_one_esl() function in mok.c while creating a new ESL variable. A remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Shim: 0.3 - 15.7

---

External links
http://access.redhat.com/security/cve/CVE-2023-40546
http://bugzilla.redhat.com/show_bug.cgi?id=2241796

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.