CVE-2023-54021
In the Linux kernel, the following vulnerability has been resolved: ext4: set goal start correctly in ext4_mb_normalize_request We need to set ac_g_ex to notify the goal start used in ext4_mb_fin…
Overview
CVE-2023-54021 is a known-severity vulnerability. It was published on December 24, 2025.
Technical description
In the Linux kernel, the following vulnerability has been resolved:
ext4: set goal start correctly in ext4_mb_normalize_request
We need to set ac_g_ex to notify the goal start used in
ext4_mb_find_by_goal. Set ac_g_ex instead of ac_f_ex in
ext4_mb_normalize_request.
Besides we should assure goal start is in range [first_data_block,
blocks_count) as ext4_mb_initialize_context does.
[ Added a check to make sure size is less than ar->pright; otherwise
we could end up passing an underflowed value of ar->pright - size to
ext4_get_group_no_and_offset(), which will trigger a BUG_ON later on.
- TYT ]
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
References
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Frequently asked questions
What is CVE-2023-54021?
CVE-2023-54021 is a known-severity vulnerability. It was published on December 24, 2025.
How severe is CVE-2023-54021?
CVSS score information is not yet available for this vulnerability. Check back as the CVE record is updated by NVD analysts.
How do I fix or remediate CVE-2023-54021?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2023-54021?
CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2023-54021 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.