Hello @Deepaklal-FT ,
Welcome to the Microsoft Q&A platform. Happy to answer your question. From the details shared by you, it appears that these are reported from Microsoft threat and vulnerability management under defender for cloud's menu.
Yes, these vulnerabilities are security issues that are seen in the Linux kernel. You can refer to the following ubuntu link for more details, https://ubuntu.com/security/notices/USN-4982-1
Recommended Solution: Update the affected packages as suggested by ubuntu article.
Similarly, you can look up for all the other vulnerabilities reported with the USN number at https://ubuntu.com/security/notices/
For #2Ubuntu Security Notification for libxml2 vulnerabilities (USN-4991-1)(7.5,9.1)
https://ubuntu.com/security/notices/USN-4991-1
Ubuntu Security Notification for GRUB 2 vulnerabilities (USN-4992-1)(7.2,8.2)
--an attacker could use this to bypass uefi(Unified Extensible Firmware Interface and is the next generation interface between
the operating system and platform firmware) secure boot restrictions.
Ubuntu Security Notification for Linux kernel vulnerabilities (USN-5000-1)(7.2,8.2)
--a local attacker could use this issue to execute arbitrary code
Ubuntu Security Notification for Linux kernel vulnerabilities (USN-4945-1)(7.2,8.2)
--A local attacker could use this to cause a denial of service (system crash)
Ubuntu Security Notification for Linux kernel vulnerabilities (USN-4979-1)(7.2,8.2)
--a local attacker could use this to cause a denial of service (system crash)
Ubuntu Security Notification for curl Vulnerabilities (USN-5412-1)(5.4,8.6)
--Successful exploitation of this vulnerability could lead to a security breach or could affect integrity, availability, and confidentiality.
Ubuntu Security Notification for NSS Vulnerability (USN-5410-1)(5,7.5)
--Successful exploitation of this vulnerability could lead to a security breach or could affect integrity, availability, and confidentiality.
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