# CVE-2025-39836: linux: In the Linux kernel, the following vulnerability has been resolved:  efi: stmm: Fix incorrect buffer allocation metho...

CVE-2025-39836 is fixed in 18 products on 1 platform, first by DEBIAN-CVE-2025-39836, released September 16, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2025-39836
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0015
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 16, 2025

## Description

In the Linux kernel, the following vulnerability has been resolved:  efi: stmm: Fix incorrect buffer allocation method  The communication buffer allocated by setup_mm_hdr() is later on passed to tee_shm_register_kernel_buf(). The latter expects those buffers to be contiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause various corruptions or BUGs, specifically since commit 9aec2fb0fd5e ("slab: allocate frozen pages"), though it was broken before as well.  Fix this by using alloc_pages_exact() instead of kmalloc().

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dtb-aarch64 opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-64kb opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-64kb sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-64kb sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-azure sles 15.7 | 6.4.0-150700.20.27.1 | [SUSE-SU-2026:0472-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0472-1.md) | Feb 12, 2026 |
| Linux | kernel-default opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-default sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-default sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-default-base opensuse-leap 16.0 | 6.12.0-160000.6.1.160000.2.4 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-default-base sles 15.7 | 6.4.0-150700.53.31.1.150700.17.21.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-default-base sles 16.0 | 6.12.0-160000.6.1.160000.2.4 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-docs opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-docs sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-docs sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-kvmsmall opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-kvmsmall sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-livepatch-SLE15-SP7-RT_Update_9 sles 15.7 | 1-150700.1.3.2 | [SUSE-SU-2026:0587-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0587-1.md) | Feb 20, 2026 |
| Linux | kernel-livepatch-SLE15-SP7_Update_9 sles 15.7 | 1-150700.15.3.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-obs-build opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-obs-build sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-obs-qa opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-obs-qa sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-rt opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-source opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-source sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-source sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-source-azure sles 15.7 | 6.4.0-150700.20.27.1 | [SUSE-SU-2026:0472-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0472-1.md) | Feb 12, 2026 |
| Linux | kernel-syms opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-syms sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-syms sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | kernel-syms-azure sles 15.7 | 6.4.0-150700.20.27.1 | [SUSE-SU-2026:0472-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0472-1.md) | Feb 12, 2026 |
| Linux | kernel-zfcpdump opensuse-leap 16.0 | 6.12.0-160000.6.1 | [OPENSUSE-SU-2025:20081-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20081-1.md) | Nov 25, 2025 |
| Linux | kernel-zfcpdump sles 15.7 | 6.4.0-150700.53.31.1 | [SUSE-SU-2026:0447-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-0447-1.md) | Feb 11, 2026 |
| Linux | kernel-zfcpdump sles 16.0 | 6.12.0-160000.6.1 | [SUSE-SU-2025:21139-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21139-1.md) | Nov 25, 2025 |
| Linux | linux Debian 13.5 (trixie) | 6.12.48-1 | [DEBIAN-CVE-2025-39836](https://patchblox.com/security/data/fix/linux/debian-cve-2025-39836.md) | Sep 16, 2025 |
| Linux | linux Debian 14 | 6.16.5-1 | [DEBIAN-CVE-2025-39836](https://patchblox.com/security/data/fix/linux/debian-cve-2025-39836.md) | Sep 16, 2025 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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