CVE-2026-31697
HighIn the Linux kernel, the following vulnerability has been resolved: crypto: ccp: Don't attempt to copy ID to userspace if PSP command failed When retrieving the ID for the CPU, don't attempt to copy the ID blob to userspace if the firmware command failed. If the failure was due to an invalid length, i.e. the userspace buffer+length was too small, copying the number of bytes _firmware_ requires will overflow the kernel-allocated buffer and leak data to userspace. BUG: KASAN: slab-out-of-bounds in instrument_copy_to_user ../include/linux/instrumented.h:129 [inline] BUG: KASAN: slab-out-of-bounds in _inline_copy_to_user ../include/linux/uaccess.h:205 [inline] BUG: KASAN: slab-out-of-bounds in _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26 Read of size 64 at addr ffff8881867f5960 by task syz.0.906/24388 CPU: 130 UID: 0 PID: 24388 Comm: syz.0.906 Tainted: G U O 7.0.0-smp-DEV #28 PREEMPTLAZY Tainted: [U]=USER, [O]=OOT_MODULE Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.62.0-0 11/19/2025 Call Trace: <TASK> dump_stack_lvl+0xc5/0x110 ../lib/dump_stack.c:120 print_address_description ../mm/kasan/report.c:378 [inline] print_report+0xbc/0x260 ../mm/kasan/report.c:482 kasan_report+0xa2/0xe0 ../mm/kasan/report.c:595 check_region_inline ../mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 ../mm/kasan/generic.c:200 instrument_copy_to_user ../include/linux/instrumented.h:129 [inline] _inline_copy_to_user ../include/linux/uaccess.h:205 [inline] _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26 copy_to_user ../include/linux/uaccess.h:236 [inline] sev_ioctl_do_get_id2+0x361/0x490 ../drivers/crypto/ccp/sev-dev.c:2222 sev_ioctl+0x25f/0x490 ../drivers/crypto/ccp/sev-dev.c:2575 vfs_ioctl ../fs/ioctl.c:51 [inline] __do_sys_ioctl ../fs/ioctl.c:597 [inline] __se_sys_ioctl+0x11d/0x1b0 ../fs/ioctl.c:583 do_syscall_x64 ../arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe0/0x800 ../arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> WARN if the driver says the command succeeded, but the firmware error code says otherwise, as __sev_do_cmd_locked() is expected to return -EIO on any firwmware error.
CVSS 3.1 score
7.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Weakness type
CWE-787CVE-2026-31697 is a Out-of-bounds Write vulnerability
What is Out-of-bounds Write?
The product writes data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.2
and later are affected. Fixed in
5.10.258,
5.15.209,
6.1.175,
6.6.136,
6.12.84,
6.18.25,
7.0.2,
7.1-rc1
and their respective stable series.
References
The following references provide additional information about CVE-2026-31697 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/06f06d88c05ce176c61fff8c72c372847b0dd2b5
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PatchKernel patch commithttps://git.kernel.org/stable/c/09427bcb1715fb20a80b6acd5156dbf15ab5c363
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PatchKernel patch commithttps://git.kernel.org/stable/c/0f1f2f9894893dc8a28af1b9e9dbc0abf453eb52
Frequently asked questions
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What is CVE-2026-31697?
CVE-2026-31697 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10 , classified as an Out-of-bounds Write flaw (CWE-787) . It affects Linux kernel versions from 5.2 onward and has been patched in 5.10.258, 5.15.209, 6.1.175 and others. CVE-2026-31697 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-31697?
CVE-2026-31697 has a CVSS score of 7.1 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. -
Is there a patch available for CVE-2026-31697?
Yes — CVE-2026-31697 has been patched. Fixed versions include 5.10.258, 5.15.209, 6.1.175 and others. If you are running Linux kernel 5.2 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-31697 actively exploited?
No — CVE-2026-31697 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Out-of-bounds Write (CWE-787)?
The product writes data past the end or before the beginning of the intended buffer. View CWE-787 on MITRE CWE →