Linux Kernel up to 6.12.16/6.13.4/6.14-rc3 mtd sst.c sst_nor_write_data state issue

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.16/6.13.4/6.14-rc3 and classified as problematic. Affected by this issue is the function sst_nor_write_data of the file drivers/mtd/spi-nor/sst.c of the component mtd. The manipulation results in state issue. This vulnerability is known as CVE-2025-21845. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 6.12.16/6.13.4/6.14-rc3. Affected is the function sst_nor_write_data of the file drivers/mtd/spi-nor/sst.c of the component mtd. The manipulation with an unknown input leads to a state issue vulnerability. CWE is classifying the issue as CWE-371. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: mtd: spi-nor: sst: Fix SST write failure 'commit 18bcb4aa54ea ("mtd: spi-nor: sst: Factor out common write operation to `sst_nor_write_data()`")' introduced a bug where only one byte of data is written, regardless of the number of bytes passed to sst_nor_write_data(), causing a kernel crash during the write operation. Ensure the correct number of bytes are written as passed to sst_nor_write_data(). Call trace: [ 57.400180] ------------[ cut here ]------------ [ 57.404842] While writing 2 byte written 1 bytes [ 57.409493] WARNING: CPU: 0 PID: 737 at drivers/mtd/spi-nor/sst.c:187 sst_nor_write_data+0x6c/0x74 [ 57.418464] Modules linked in: [ 57.421517] CPU: 0 UID: 0 PID: 737 Comm: mtd_debug Not tainted 6.12.0-g5ad04afd91f9 #30 [ 57.429517] Hardware name: Xilinx Versal A2197 Processor board revA - x-prc-02 revA (DT) [ 57.437600] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 57.444557] pc : sst_nor_write_data+0x6c/0x74 [ 57.448911] lr : sst_nor_write_data+0x6c/0x74 [ 57.453264] sp : ffff80008232bb40 [ 57.456570] x29: ffff80008232bb40 x28: 0000000000010000 x27: 0000000000000001 [ 57.463708] x26: 000000000000ffff x25: 0000000000000000 x24: 0000000000000000 [ 57.470843] x23: 0000000000010000 x22: ffff80008232bbf0 x21: ffff000816230000 [ 57.477978] x20: ffff0008056c0080 x19: 0000000000000002 x18: 0000000000000006 [ 57.485112] x17: 0000000000000000 x16: 0000000000000000 x15: ffff80008232b580 [ 57.492246] x14: 0000000000000000 x13: ffff8000816d1530 x12: 00000000000004a4 [ 57.499380] x11: 000000000000018c x10: ffff8000816fd530 x9 : ffff8000816d1530 [ 57.506515] x8 : 00000000fffff7ff x7 : ffff8000816fd530 x6 : 0000000000000001 [ 57.513649] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ 57.520782] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0008049b0000 [ 57.527916] Call trace: [ 57.530354] sst_nor_write_data+0x6c/0x74 [ 57.534361] sst_nor_write+0xb4/0x18c [ 57.538019] mtd_write_oob_std+0x7c/0x88 [ 57.541941] mtd_write_oob+0x70/0xbc [ 57.545511] mtd_write+0x68/0xa8 [ 57.548733] mtdchar_write+0x10c/0x290 [ 57.552477] vfs_write+0xb4/0x3a8 [ 57.555791] ksys_write+0x74/0x10c [ 57.559189] __arm64_sys_write+0x1c/0x28 [ 57.563109] invoke_syscall+0x54/0x11c [ 57.566856] el0_svc_common.constprop.0+0xc0/0xe0 [ 57.571557] do_el0_svc+0x1c/0x28 [ 57.574868] el0_svc+0x30/0xcc [ 57.577921] el0t_64_sync_handler+0x120/0x12c [ 57.582276] el0t_64_sync+0x190/0x194 [ 57.585933] ---[ end trace 0000000000000000 ]--- [[email protected]: add Cc stable tag]

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-21845 since 12/29/2024. The exploitability is told to be difficult. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/17/2026).

Upgrading to version 6.12.17, 6.13.5 or 6.14-rc4 eliminates this vulnerability. Applying the patch bb1accc7e0f688886f0c634f2e878b8ac4ee6a58/9553391f32f8c43e12fc7c04e1035160b5ea20bf/539bd20352832b9244238a055eb169ccf1c41ff6 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 vulnerability database at CERT Bund (WID-SEC-2025-0545). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Siemens SIMATIC S7
• RESF Rocky Linux
• SolarWinds Security Event Manager
• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.13.0
• 6.13.1
• 6.13.2
• 6.13.3
• 6.13.4
• 6.14-rc1
• 6.14-rc2
• 6.14-rc3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

Threat Intelligenceinfo

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Sourcesinfo

Entryinfo

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