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TI-2022-11370 Aliases CVE-2022-28736GHSA-ff72-fwj3-6gh6

Use after free in GNU GRUB

Priority LOW 36CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 5 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

There's a use-after-free vulnerability in grub_cmd_chainloader() function; The chainloader command is used to boot up operating systems that doesn't support multiboot and do not have direct support from GRUB2. When executing chainloader more than once a use-after-free vulnerability is triggered. If an attacker can control the GRUB2's memory allocation pattern sensitive data may be exposed and arbitrary code execution can be achieved.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00286 21st percentileScored 2026-11-07
Fix Partial GNU GRUB (GNU Project): 2.06-3Red Hat: 5 advisoriesRed Hat: 5 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
GNUGNU GRUBbefore 2.06-32.06-3Patch availableCNA
  • GNU GRUB VendorGNU Affected before 2.06-3 Fixed in 2.06-3 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:*2.00 to before 2.06-3VulnerableGNU
  • cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:* Versions 2.00 to before 2.06-3 Vulnerable ·GNU

Remediation

  • Fix · CNA GNU GRUB (GNU Project) Fixed in 2.06-3

Red Hat 5 advisories

  • RHSA-2022:5100 Released 2022-06-16 · Red Hat rating Important
    grub2, mokutil, shim, and shim-unsigned-x64 security update
    • Red Hat CodeReady Linux Builder EUS (v. 8.2) shim-unsigned-x64-15.6-1.el8
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.2) grub2-1:2.02-87.el8_2.10, grub2-common-1:2.02-87.el8_2.10, grub2-efi-aa64-1:2.02-87.el8_2.10 +20
  • RHSA-2022:5095 Released 2022-06-16 · Red Hat rating Important
    grub2, mokutil, shim, and shim-unsigned-x64 security update
    • Red Hat Enterprise Linux BaseOS (v. 8) grub2-1:2.02-123.el8_6.8, grub2-common-1:2.02-123.el8_6.8, grub2-efi-aa64-1:2.02-123.el8_6.8 +20
    • Red Hat Enterprise Linux CRB (v. 8) shim-unsigned-x64-15.6-1.el8
  • RHSA-2022:5099 Released 2022-06-16 · Red Hat rating Important
    grub2, mokutil, shim, and shim-unsigned-x64 security update
    • Red Hat CodeReady Linux Builder (v. 9) shim-unsigned-x64-15.6-1.el9
    • Red Hat Enterprise Linux BaseOS (v. 9) grub2-1:2.06-27.el9_0.7, grub2-common-1:2.06-27.el9_0.7, grub2-efi-aa64-1:2.06-27.el9_0.7 +16
Show 2 more Red Hat advisories
  • RHSA-2022:5096 Released 2022-06-16 · Red Hat rating Important
    grub2, mokutil, shim, and shim-unsigned-x64 security update
    • Red Hat Enterprise Linux BaseOS EUS (v.8.4) grub2-1:2.02-99.el8_4.9, grub2-common-1:2.02-99.el8_4.9, grub2-efi-aa64-1:2.02-99.el8_4.9 +20
    • Red Hat Enterprise Linux CRB EUS (v.8.4) shim-unsigned-x64-15.6-1.el8
  • RHSA-2022:5098 Released 2022-06-16 · Red Hat rating Important
    grub2, mokutil, and shim security update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.1) grub2-1:2.02-87.el8_1.10, grub2-common-1:2.02-87.el8_1.10, grub2-efi-aa64-modules-1:2.02-87.el8_1.10 +17

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    GNU GRUB 2.06-3

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2022-11367 Integer underflow in GNU GRUBPriority MEDIUM 40
    • TI-2022-11368 Out-of-bounds write in GNU GRUBPriority LOW 37
    • TI-2022-11369 The GRUB2's shim_lock verifier allows non-kernel files to be loaded on shim-powered…Priority LOW 36
    Show all 4 records →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2022:5095
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2022:5099
Red Hat Enterprise Linux BaseOS E4S (v. 8.1)Fixed RHSA-2022:5098
Red Hat Enterprise Linux BaseOS EUS (v. 8.2)Fixed RHSA-2022:5100
Red Hat Enterprise Linux BaseOS EUS (v.8.4)Fixed RHSA-2022:5096
Not affected: 9 products
  • Red Hat CodeReady Linux Builder (v. 9)
  • Red Hat CodeReady Linux Builder EUS (v. 8.2)
  • Red Hat Enterprise Linux BaseOS (v. 8)
  • Red Hat Enterprise Linux BaseOS (v. 9)
  • Red Hat Enterprise Linux BaseOS E4S (v. 8.1)
  • Red Hat Enterprise Linux BaseOS EUS (v. 8.2)
  • Red Hat Enterprise Linux BaseOS EUS (v.8.4)
  • Red Hat Enterprise Linux CRB (v. 8)
  • Red Hat Enterprise Linux CRB EUS (v.8.4)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-28736
  2. 2026-10-03 Alias added: GHSA-ff72-fwj3-6gh6

References

Advisory 2

Other 1

  • TI-2023-04324 Grub2: out-of-bounds write at fs/ntfs.c may lead to unsigned code execution CVSS 3.1HIGH 7.8
  • TI-2015-06891 Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximate… CVSS 3.1HIGH 7.4
  • TI-2024-37620 Heap-based buffer overflow in GNU GRUB2 CVSS 3.1HIGH 8.8
  • TI-2022-11367 Integer underflow in GNU GRUB CVSS 3.1HIGH 8.1
  • TI-2022-02403 Heap-based buffer overflow in grub2 CVSS 3.1HIGH 8.6
  • TI-2020-08612 Buffer overflow in Grub CVSS 3.1HIGH 8.2
See all 47 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences