USN-4992-1: grub2-signed Ubuntu

CVSS: UnknownPublished
Published 18-06-2021Last modified 27-04-2026

Vulnerability summary

USN-4992-1 is a vulnerability in grub2-signed Ubuntu with no CVSS score yet.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
Not scored
0%100%
No EPSS score yet
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 6 · Downstream 0 · Related 6

Timeline

  1. 18-06-2021
    PublishedVulnerability first disclosed.
  2. 27-04-2026
    Last modifiedVulnerability information updated.

Description

grub2-signed, grub2-unsigned vulnerabilities Máté Kukri discovered that the acpi command in GRUB 2 allowed privileged users to load crafted ACPI tables when secure boot is enabled. An attacker could use this to bypass UEFI Secure Boot restrictions. (CVE-2020-14372) Chris Coulson discovered that the rmmod command in GRUB 2 contained a use- after-free vulnerability. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-25632) Chris Coulson discovered that a buffer overflow existed in the command line parser in GRUB 2. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-27749) It was discovered that the cutmem command in GRUB 2 did not honor secure boot locking. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-27779) It was discovered that the option parser in GRUB 2 contained a heap overflow vulnerability. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2021-20225) It was discovered that the menu rendering implementation in GRUB 2 did not properly calculate the amount of memory needed in some situations, leading to out-of-bounds writes. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2021-20233)

CVSS metrics

Risk metrics not yet published.

EPSS trend

No EPSS score has been published for this record yet.

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu2 products
  • grub2-signed< 1.167~18.04.5 | < 1.167.2
  • grub2-unsigned< 2.04-1ubuntu44.1.2 | < 2.04-1ubuntu44.2

1 vendor · 2 products

References

7 links