LiveActive security incident?Get immediate response
CVE Record

CVE-2025-38549: efivarfs: Fix memory leak of efivarfs_fs_info in fs_context error paths

In the Linux kernel, the following vulnerability has been resolved: efivarfs: Fix memory leak of efivarfs_fs_info in fs_context error paths When processing mount options, efivarfs allocates efivarfs_fs_info (sfi) early in fs_context initialization. However, sfi is associated with the superblock and typically freed when the superblock is destroyed. If the fs_context is released (final put) before fill_super is called—such as on error paths or during reconfiguration—the sfi structure would leak, as ownership never transfers to the superblock. Implement the .free callback in efivarfs_context_ops to ensure any allocated sfi is properly freed if the fs_context is torn down before fill_super, preventing this memory leak.

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

Security readout for executives and security teams

Plain-English summary

CVE-2025-38549 is a Linux kernel memory leak in efivarfs, the filesystem used for EFI variables. Certain mount-option error or reconfiguration paths can allocate kernel memory and fail to free it. The public record does not provide CVSS, real-world impact, or exploitation evidence.

Executive priority

Treat as routine kernel maintenance unless vendor advisories add stronger impact detail. Patch through normal Linux kernel update channels, with higher priority for shared or privileged multi-user systems where repeated kernel resource leaks matter more.

Technical view

efivarfs allocates efivarfs_fs_info during fs_context initialization. If the fs_context is released before fill_super transfers ownership to the superblock, the allocation leaks. The fix adds a free callback in efivarfs_context_ops to release the structure on teardown before fill_super.

Likely exposure

Exposure is most relevant to Linux systems running affected kernel builds with efivarfs available. The bundle lists Linux kernel version markers including 6.7, 6.12.40, 6.15.8, and 6.16, but does not fully explain range semantics.

Exploitation context

The source bundle does not cite active exploitation, public exploit availability, or KEV listing. Based on the description, this is a kernel memory-leak issue on mount error or reconfiguration paths, not a disclosed code-execution flaw.

Researcher notes

The record is sparse: no CVSS, CWE, exploit status, or detailed affected range semantics are provided. Analysis should avoid overstating exploitability. The primary technical anchor is the efivarfs fs_context ownership bug and the stable commits fixing teardown cleanup.

Mitigation direction

  • Update to a kernel build containing the referenced stable fixes.
  • Check Linux distribution advisories for the exact fixed package version.
  • Prioritize systems exposing efivarfs and kernel mount or reconfiguration paths.
  • Review privileged access that can trigger filesystem mount operations.
  • Monitor vendor guidance because no separate workaround is named.

Validation and detection

  • Inventory running kernel versions across Linux assets.
  • Confirm whether efivarfs is enabled or mounted on target systems.
  • Compare installed kernel packages against distribution fixed versions.
  • Verify the referenced stable commits are present in custom kernels.
  • Track any later CVSS, CWE, or advisory updates.
Prepared
Confidence
medium
Sources
5

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-2025-38549 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
4Source 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
LinuxLinux5329aa5101f73c451bcd48deaf3f296685849d9c, 5329aa5101f73c451bcd48deaf3f296685849d9c, 5329aa5101f73c451bcd48deaf3f296685849d9cunaffected
LinuxLinux6.7, 0, 6.12.40, 6.15.8, 6.16affected
Weakness

CWE details

No CWE listed

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