LiveActive security incident?Get immediate response
CVE Record

CVE-2024-39477: mm/hugetlb: do not call vma_add_reservation upon ENOMEM

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: do not call vma_add_reservation upon ENOMEM sysbot reported a splat [1] on __unmap_hugepage_range(). This is because vma_needs_reservation() can return -ENOMEM if allocate_file_region_entries() fails to allocate the file_region struct for the reservation. Check for that and do not call vma_add_reservation() if that is the case, otherwise region_abort() and region_del() will see that we do not have any file_regions. If we detect that vma_needs_reservation() returned -ENOMEM, we clear the hugetlb_restore_reserve flag as if this reservation was still consumed, so free_huge_folio() will not increment the resv count. [1] https://lore.kernel.org/linux-mm/0000000000004096100617c58d54@google.com/T/#ma5983bc1ab18a54910da83416b3f89f3c7ee43aa

HighCVSS 7.8Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

A Linux huge-page memory management flaw can corrupt reservation bookkeeping when memory allocation fails. A local, low-privileged user may be able to trigger serious confidentiality, integrity, or availability impact. The supplied evidence does not establish remote reachability or real-world exploitation.

Executive priority

Prioritize internet-facing multi-user systems, shared compute platforms, and hosts permitting untrusted local code. Patch through normal emergency kernel processes after compatibility testing. Lower priority may be reasonable where local execution is tightly controlled, but the high potential impact warrants prompt exposure confirmation.

Technical view

When vma_needs_reservation() returns -ENOMEM because a file_region allocation fails, vulnerable code still calls vma_add_reservation(). Later reservation cleanup encounters missing file-region records, producing an unmap failure. The kernel fix skips that call and clears hugetlb_restore_reserve so reservation counts remain consistent.

Likely exposure

Exposure requires a vulnerable Linux kernel and local authenticated access, with the affected hugetlb reservation path reachable. The bundle identifies the 6.9 development line through 6.10-related version data, but its exact range encoding is ambiguous. Confirm applicability through kernel or distribution guidance.

Exploitation context

The CVSS vector rates exploitation as local, low complexity, requiring low privileges, without user interaction. Potential confidentiality, integrity, and availability impacts are high. CISA KEV status is false, and the supplied sources provide no evidence of active exploitation.

Researcher notes

The issue was reported by syzbot as a failure in __unmap_hugepage_range(). The relevant error path begins when allocate_file_region_entries() cannot allocate a file_region structure. No CWE, proof of concept, confirmed exploit, or complete distribution-specific fixed-version matrix is supplied.

Mitigation direction

  • Apply the appropriate vendor or distribution kernel update containing the referenced fix.
  • Check vendor advisories because the supplied affected-version range is ambiguous.
  • Restrict untrusted local access until affected kernels are updated.
  • Follow vendor guidance for any temporary hugetlb-specific mitigation.

Validation and detection

  • Inventory running kernel versions across hosts, containers, and virtual-machine images.
  • Compare each kernel build against its distribution's CVE-2024-39477 advisory.
  • Verify the installed kernel includes the applicable referenced stable fix.
  • Reboot updated systems and confirm the running kernel matches the patched package.
  • Review kernel logs for hugetlb reservation or unmap failures.
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-2024-39477 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
High
CVSS
7.8 (3.1)
Known Exploited
No
Published

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

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.

1CVSS vectors
3Timeline events
2ADP providers
3Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.8CVSS 3.1HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Linux

Vulnerability scoring details

Base CVSS 3.1 score

7.8High
CVSS 3.1 vector shape for CVE-2024-39477Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

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.

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxdf7a6d1f64056aec572162c5d35ed9ff86ece6f3, df7a6d1f64056aec572162c5d35ed9ff86ece6f3unaffected
LinuxLinux6.9, 0, 6.9.5, 6.10affected
Weakness

CWE details

No CWE listed

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