Linux Kernel up to 6.6.98/6.12.38/6.15.6/6.16-rc4 dma_buf_vmap memory corruption

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6.6$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.6.98/6.12.38/6.15.6/6.16-rc4. This affects the function dma_buf_vmap. The manipulation results in memory corruption. This vulnerability is cataloged as CVE-2025-38449. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.6.98/6.12.38/6.15.6/6.16-rc4. Affected is the function dma_buf_vmap. 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: drm/gem: Acquire references on GEM handles for framebuffers A GEM handle can be released while the GEM buffer object is attached to a DRM framebuffer. This leads to the release of the dma-buf backing the buffer object, if any. [1] Trying to use the framebuffer in further mode-setting operations leads to a segmentation fault. Most easily happens with driver that use shadow planes for vmap-ing the dma-buf during a page flip. An example is shown below. [ 156.791968] ------------[ cut here ]------------ [ 156.796830] WARNING: CPU: 2 PID: 2255 at drivers/dma-buf/dma-buf.c:1527 dma_buf_vmap+0x224/0x430 [...] [ 156.942028] RIP: 0010:dma_buf_vmap+0x224/0x430 [ 157.043420] Call Trace: [ 157.045898] <TASK> [ 157.048030] ? show_trace_log_lvl+0x1af/0x2c0 [ 157.052436] ? show_trace_log_lvl+0x1af/0x2c0 [ 157.056836] ? show_trace_log_lvl+0x1af/0x2c0 [ 157.061253] ? drm_gem_shmem_vmap+0x74/0x710 [ 157.065567] ? dma_buf_vmap+0x224/0x430 [ 157.069446] ? __warn.cold+0x58/0xe4 [ 157.073061] ? dma_buf_vmap+0x224/0x430 [ 157.077111] ? report_bug+0x1dd/0x390 [ 157.080842] ? handle_bug+0x5e/0xa0 [ 157.084389] ? exc_invalid_op+0x14/0x50 [ 157.088291] ? asm_exc_invalid_op+0x16/0x20 [ 157.092548] ? dma_buf_vmap+0x224/0x430 [ 157.096663] ? dma_resv_get_singleton+0x6d/0x230 [ 157.101341] ? __pfx_dma_buf_vmap+0x10/0x10 [ 157.105588] ? __pfx_dma_resv_get_singleton+0x10/0x10 [ 157.110697] drm_gem_shmem_vmap+0x74/0x710 [ 157.114866] drm_gem_vmap+0xa9/0x1b0 [ 157.118763] drm_gem_vmap_unlocked+0x46/0xa0 [ 157.123086] drm_gem_fb_vmap+0xab/0x300 [ 157.126979] drm_atomic_helper_prepare_planes.part.0+0x487/0xb10 [ 157.133032] ? lockdep_init_map_type+0x19d/0x880 [ 157.137701] drm_atomic_helper_commit+0x13d/0x2e0 [ 157.142671] ? drm_atomic_nonblocking_commit+0xa0/0x180 [ 157.147988] drm_mode_atomic_ioctl+0x766/0xe40 [...] [ 157.346424] ---[ end trace 0000000000000000 ]--- Acquiring GEM handles for the framebuffer's GEM buffer objects prevents this from happening. The framebuffer's cleanup later puts the handle references. Commit 1a148af06000 ("drm/gem-shmem: Use dma_buf from GEM object instance") triggers the segmentation fault easily by using the dma-buf field more widely. The underlying issue with reference counting has been present before. v2: - acquire the handle instead of the BO (Christian) - fix comment style (Christian) - drop the Fixes tag (Christian) - rename err_ gotos - add missing Link tag

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2025-38449 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 01/03/2026).

The vulnerability scanner Nessus provides a plugin with the ID 264525 (RHEL 9 : kernel (RHSA-2025:15661)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.99, 6.12.39, 6.15.7 or 6.16-rc5 eliminates this vulnerability. Applying the patch cb4c956a15f8b7f870649454771fc3761f504b5f/08480e285c6a82ce689008d643e4a51db0aaef8b/3cf520d9860d4ec9f7f32068825da31f18dd3f25/5307dce878d4126e1b375587318955bd019c3741 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 (264525) and CERT Bund (WID-SEC-2025-1653). 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
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Dell Avamar
  • Open Source Linux Kernel
  • Dell NetWorker
  • Dell Secure Connect Gateway

Productinfo

Type

Vendor

Name

Version

License

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: 264525
Nessus Name: RHEL 9 : kernel (RHSA-2025:15661)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.99/6.12.39/6.15.7/6.16-rc5
Patch: cb4c956a15f8b7f870649454771fc3761f504b5f/08480e285c6a82ce689008d643e4a51db0aaef8b/3cf520d9860d4ec9f7f32068825da31f18dd3f25/5307dce878d4126e1b375587318955bd019c3741

Timelineinfo

04/16/2025 CVE reserved
07/25/2025 +100 days Advisory disclosed
07/25/2025 +0 days VulDB entry created
01/03/2026 +162 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38449 (🔒)
GCVE (CVE): GCVE-0-2025-38449
GCVE (VulDB): GCVE-100-317754
CERT Bund: WID-SEC-2025-1653 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 07/25/2025 19:35
Updated: 01/03/2026 23:51
Changes: 07/25/2025 19:35 (58), 07/30/2025 02:00 (1), 08/22/2025 19:43 (7), 09/11/2025 20:57 (2), 09/15/2025 05:23 (1), 09/29/2025 02:13 (1), 11/02/2025 13:58 (1), 11/17/2025 06:19 (1), 11/20/2025 02:24 (12), 01/03/2026 23:51 (1)
Complete: 🔍
Cache ID: 216::103

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

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