CVE-2025-21845

CVE-2025-21845 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

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]

Frequently asked questions

What is CVE-2025-21845?
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]
How severe is CVE-2025-21845?
CVE-2025-21845 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21845 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21845?
CVE-2025-21845 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-21845?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21845 have an EU (EUVD) identifier?
Yes. CVE-2025-21845 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-6400.
When was CVE-2025-21845 published?
CVE-2025-21845 was published on 2025-03-12 and last updated on 2026-06-17.

References

Affected products (4)

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