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NVD / CVE Program· CNA redhat

CVE-2025-61663: Grub2: missing unregister call for normal commands may lead to use-after-free

Noroxi assessment

Priority: Monitor (action score 19/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.13% (FIRST EPSS).
  • Someone with local access to the system can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: azl3 grub2 2.06-25 on Azure Linux 3.0 2.06-26; azl3 grub2 2.06-26 on Azure Linux 3.0 2.06-26; cbl2 grub2 2.06-15 on CBL Mariner 2.0 2.06-16.

Low priority for now. Upgrade to azl3 grub2 2.06-25 on Azure Linux 3.0 2.06-26; azl3 grub2 2.06-26 on Azure Linux 3.0 2.06-26; cbl2 grub2 2.06-15 on CBL Mariner 2.0 2.06-16 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A vulnerability has been identified in the GRUB2 bootloader's normal command that poses an immediate Denial of Service (DoS) risk. This flaw is a Use-after-Free issue, caused because the normal command is not properly unregistered when the module is unloaded. An attacker who can execute this command can force the system to access memory locations that are no longer valid. Successful exploitation leads directly to system instability, which can result in a complete crash and halt system availability. Impact on the data integrity and confidentiality is also not discarded.

MediumCVSS 4.9 · v3.1—No exploit Fix available
Published
Nov 18, 2025
Updated
Oct 18, 2026
EPSS
0.1% · 3th percentile

Report tools

JSON

Action score

19

Monitor

Low priority for now.

CVSS
19 / 40 · 4.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · redhat
4.9
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-61663

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • GNU grub2

    • up to and including 2.14affected · semver

  • Red Hat Red Hat Enterprise Linux 10

    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 7

    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 8

    • all versionsaffected

  • Red Hat Red Hat Enterprise Linux 9

    • all versionsaffected

  • Red Hat Red Hat OpenShift Container Platform 4

    • all versionsaffected
    • all versionsaffected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12grub2from 0—
Debian:14grub2before 2.14-12.14-1
openSUSE:Leap 15.6grub2before 2.12-150600.8.44.22.12-150600.8.44.2
openSUSE:Leap 16.0grub2before 2.12-160000.3.12.12-160000.3.1
openSUSE:Tumbleweedgrub2before 2.12-67.12.12-67.1
SUSE:Linux Enterprise Micro 5.2grub2before 2.04-150300.22.61.12.04-150300.22.61.1
SUSE:Linux Enterprise Micro 5.3grub2before 2.06-150400.11.66.12.06-150400.11.66.1
SUSE:Linux Enterprise Micro 5.5grub2before 2.06-150500.29.59.12.06-150500.29.59.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6grub2before 2.12-150600.8.44.22.12-150600.8.44.2
SUSE:Linux Enterprise Module for Basesystem 15 SP7grub2before 2.12-150700.19.19.12.12-150700.19.19.1
SUSE:Linux Enterprise Server 16.0grub2before 2.12-160000.3.12.12-160000.3.1
SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5grub2before 2.02-193.12.02-193.1
SUSE:Linux Micro 6.1grub2before 2.12-slfo.1.1_3.12.12-slfo.1.1_3.1

Same product

gnu: all records

Other highest-scoring records for the same primary product.

  • CVE-2024-56737GNU GRUB (aka GRUB2) through 2.12 has a heap-based buffer overflow in fs/hfs.c via crafted sblock data in an HFS filesystem.
    35Monitor
  • CVE-2022-2601A buffer overflow was found in grub_font_construct_glyph().
    34Monitor
  • CVE-2020-10713A flaw was found in grub2, prior to version 2.06.
    33Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2025-61661Nov 18, 2025 · Grub2: grub2: out-of-bounds write via malicious usb device
    19Monitor
  • ← EarlierCVE-2025-61662Nov 18, 2025 · Grub2: missing unregister call for gettext command may lead to use-after-free
    31Monitor
  • Later →CVE-2025-61664Nov 18, 2025 · Grub2: missing unregister call for normal_exit command may lead to use-after-free
    19Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
azl3 grub2 2.06-25 on Azure Linux 3.02.06-26 · CBL-Mariner ReleasesMicrosoft (MSRC)
azl3 grub2 2.06-26 on Azure Linux 3.02.06-26 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 grub2 2.06-15 on CBL Mariner 2.02.06-16 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 grub2 2.06-16 on CBL Mariner 2.02.06-16 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:grub22.14-1 · Debian:14Package registry (OSV)
opensuse:grub22.12-150600.8.44.2 · openSUSE:Leap 15.6Package registry (OSV)
suse:grub22.12-150600.8.44.2 · SUSE:Linux Enterprise Module for Basesystem 15 SP6Package registry (OSV)
suse:grub22.12-slfo.1.1_3.1 · SUSE:Linux Micro 6.1Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2025-547700 days apartGrub2: use-after-free in net_set_vlan
    19Monitor
  • CVE-2025-547710 days apartGrub2: use-after-free in grub_file_close()
    19Monitor
  • CVE-2025-616640 days apartGrub2: missing unregister call for normal_exit command may lead to use-after-free
    19Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • No account or password is required.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
low · data can be read
Integrity
low · data or configuration can be modified
Availability
low · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
Low
Availability impact
Low

Weakness class (CWE)

CWE-825 · Expired Pointer Dereference

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records