LiveActive security incident?Get immediate response
CVE Record

CVE-2023-53450: ext4: remove a BUG_ON in ext4_mb_release_group_pa()

In the Linux kernel, the following vulnerability has been resolved: ext4: remove a BUG_ON in ext4_mb_release_group_pa() If a malicious fuzzer overwrites the ext4 superblock while it is mounted such that the s_first_data_block is set to a very large number, the calculation of the block group can underflow, and trigger a BUG_ON check. Change this to be an ext4_warning so that we don't crash the kernel.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This Linux kernel ext4 flaw can turn a corrupted mounted filesystem superblock into a kernel crash instead of a warning. Business impact is mainly availability: affected Linux systems could reboot or stop if the condition is triggered. The sources do not show remote exploitation, privilege escalation, CVSS scoring, or CISA KEV listing.

Executive priority

Treat as a normal but real kernel availability risk. It is not supported as remotely exploitable or actively exploited, but kernel crashes can disrupt critical workloads. Patch during the next maintenance cycle, faster for systems handling untrusted storage media or disk images.

Technical view

In ext4_mb_release_group_pa(), an oversized s_first_data_block in a mounted ext4 superblock can cause block group calculation underflow and hit BUG_ON. The upstream fix replaces the crash-triggering BUG_ON with ext4_warning. The affected range in the bundle spans Linux 2.6.25 through 6.4, with stable kernel commit references provided.

Likely exposure

Exposure is most relevant to Linux systems using ext4 where an attacker or faulty process can alter a mounted filesystem superblock or present risky ext4 media/images. General remote exposure is not supported by the provided sources. Systems with strict block-device access controls have lower practical exposure.

Exploitation context

The bundle describes discovery through a malicious fuzzer overwriting the ext4 superblock while mounted. It does not cite active exploitation, public weaponization, CISA KEV inclusion, or a network attack path. Triggering appears dependent on local filesystem or block-device influence.

Researcher notes

Key evidence is narrow: a mounted ext4 superblock with a very large s_first_data_block can underflow group calculation and trigger BUG_ON. The fix changes the failure mode to warning. No CWE, CVSS, exploit status, or distro-specific fixed package data is provided in the bundle.

Mitigation direction

  • Apply vendor Linux kernel updates containing the referenced ext4 fix.
  • Prioritize systems mounting untrusted media, tenant disk images, or externally supplied ext4 volumes.
  • Restrict raw block-device access to trusted administrators and services.
  • Avoid mounting untrusted ext4 filesystems on production hosts where feasible.
  • Check Linux distribution advisories for fixed package versions and reboot requirements.

Validation and detection

  • Inventory Linux hosts and identify kernels in the affected version range.
  • Confirm whether ext4 filesystems are mounted on production or multi-tenant systems.
  • Verify the running kernel includes one of the referenced stable fixes or vendor backport.
  • Review access controls for block devices and filesystem mounting workflows.
  • Check monitoring for historical kernel BUG or panic events involving ext4.
Prepared
Confidence
medium
Sources
11

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2023-53450 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
0ADP providers
10Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxc9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55a, c9de560ded61faa5b754137b7753da252391c55aunaffected
LinuxLinux2.6.25, 0, 4.14.315, 4.19.283, 5.4.243, 5.10.180, 5.15.112, 6.1.29, 6.2.16, 6.3.3, 6.4affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.