Linux Kernel up to 6.15.3 HugeTLB Page __split_vma memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.15.3. This affects the function __split_vma of the component HugeTLB Page Handler. The manipulation results in memory corruption. This vulnerability is reported as CVE-2025-38084. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.15.3. It has been classified as critical. Affected is the function __split_vma of the component HugeTLB Page Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: unshare page tables during VMA split, not before Currently, __split_vma() triggers hugetlb page table unsharing through vm_ops->may_split(). This happens before the VMA lock and rmap locks are taken - which is too early, it allows racing VMA-locked page faults in our process and racing rmap walks from other processes to cause page tables to be shared again before we actually perform the split. Fix it by explicitly calling into the hugetlb unshare logic from __split_vma() in the same place where THP splitting also happens. At that point, both the VMA and the rmap(s) are write-locked. An annoying detail is that we can now call into the helper hugetlb_unshare_pmds() from two different locking contexts: 1. from hugetlb_split(), holding: - mmap lock (exclusively) - VMA lock - file rmap lock (exclusively) 2. hugetlb_unshare_all_pmds(), which I think is designed to be able to call us with only the mmap lock held (in shared mode), but currently only runs while holding mmap lock (exclusively) and VMA lock Backporting note: This commit fixes a racy protection that was introduced in commit b30c14cd6102 ("hugetlb: unshare some PMDs when splitting VMAs"); that commit claimed to fix an issue introduced in 5.13, but it should actually also go all the way back. [[email protected]: v2]

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2025-38084 since 04/16/2025. The exploitability is told to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 01/30/2026).

The vulnerability scanner Nessus provides a plugin with the ID 243500 (Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2025-1111)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.239, 5.15.186, 6.1.142, 6.6.95, 6.12.35, 6.15.4 or 6.16-rc1 eliminates this vulnerability. Applying the patch e8847d18cd9fff1edbb45e963d9141273c3b539c/366298f2b04d2bf1f2f2b7078405bdf9df9bd5d0/2511ac64bc1617ca716d3ba8464e481a647c1902/af6cfcd0efb7f051af221c418ec8b37a10211947/9cf5b2a3b72c23fb7b84736d5d19ee6ea718762b/8a21d5584826f4880f45bbf8f72375f4e6c0ff2a/081056dc00a27bccb55ccc3c6f230a3d5fd3f7e0 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (243500), EUVD (EUVD-2025-19449) and CERT Bund (WID-SEC-2025-1417). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • IBM DataPower Gateway
  • Dell NetWorker

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 243500
Nessus Name: Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2025-1111)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.239/5.15.186/6.1.142/6.6.95/6.12.35/6.15.4/6.16-rc1
Patch: e8847d18cd9fff1edbb45e963d9141273c3b539c/366298f2b04d2bf1f2f2b7078405bdf9df9bd5d0/2511ac64bc1617ca716d3ba8464e481a647c1902/af6cfcd0efb7f051af221c418ec8b37a10211947/9cf5b2a3b72c23fb7b84736d5d19ee6ea718762b/8a21d5584826f4880f45bbf8f72375f4e6c0ff2a/081056dc00a27bccb55ccc3c6f230a3d5fd3f7e0

Timelineinfo

04/16/2025 CVE reserved
06/28/2025 +73 days Advisory disclosed
06/28/2025 +0 days VulDB entry created
01/30/2026 +216 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38084 (🔒)
GCVE (CVE): GCVE-0-2025-38084
GCVE (VulDB): GCVE-100-314322
EUVD: 🔒
CERT Bund: WID-SEC-2025-1417 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 06/28/2025 12:33
Updated: 01/30/2026 23:21
Changes: 06/28/2025 12:33 (59), 06/28/2025 13:35 (1), 07/21/2025 14:32 (7), 07/30/2025 09:48 (1), 08/05/2025 11:28 (2), 08/05/2025 15:27 (1), 10/14/2025 17:50 (1), 12/19/2025 00:31 (11), 01/30/2026 23:21 (1)
Complete: 🔍
Cache ID: 216:AC0:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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