How severe is CVE-2022-28735?

CVE-2022-28735 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2022-28735 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-28735?

CVE-2022-28735 affects Gnu Grub2. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-28735?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2022-28735 published?

CVE-2022-28735 was published on 2023-07-20 and last updated on 2026-06-17.

CVE-2022-28735

CVE-2022-28735 is a medium-severity vulnerability in Gnu Grub2 with a CVSS 3.x base score of 6.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Gnu Grub2
Published: 2023-07-20
Last modified: 2026-06-17

Description

The GRUB2's shim_lock verifier allows non-kernel files to be loaded on shim-powered secure boot systems. Allowing such files to be loaded may lead to unverified code and modules to be loaded in GRUB2 breaking the secure boot trust-chain.

Frequently asked questions

What is CVE-2022-28735?: The GRUB2's shim_lock verifier allows non-kernel files to be loaded on shim-powered secure boot systems. Allowing such files to be loaded may lead to unverified code and modules to be loaded in GRUB2 breaking the secure boot trust-chain.
How severe is CVE-2022-28735?: CVE-2022-28735 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2022-28735 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-28735?: CVE-2022-28735 affects Gnu Grub2. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-28735?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-28735 published?: CVE-2022-28735 was published on 2023-07-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:*

More vulnerabilities in Gnu Grub2

CVE-2024-56737 — High (CVSS 8.8): GNU GRUB (aka GRUB2) through 2.12 has a heap-based buffer overflow in fs/hfs.c via crafted sblock data in an HFS…
CVE-2022-2601 — High (CVSS 8.6): A buffer overflow was found in grub_font_construct_glyph(). A malicious crafted pf2 font can lead to an overflow when…
CVE-2021-20233 — High (CVSS 8.2): A flaw was found in grub2 in versions prior to 2.06. Setparam_prefix() in the menu rendering code performs a length…
CVE-2020-25632 — High (CVSS 8.2): A flaw was found in grub2 in versions prior to 2.06. The rmmod implementation allows the unloading of a module used as…
CVE-2020-10713 — High (CVSS 8.2): A flaw was found in grub2, prior to version 2.06. An attacker may use the GRUB 2 flaw to hijack and tamper the GRUB…
CVE-2022-28734 — High (CVSS 8.1): Out-of-bounds write when handling split HTTP headers; When handling split HTTP headers, GRUB2 HTTP code accidentally…

All CVEs affecting Gnu Grub2 →