CVE-2026-31698

Source
https://cve.org/CVERecord?id=CVE-2026-31698
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31698.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-31698
Downstream
Related
Published
2026-05-01T13:55:58Z
Modified
2026-08-27T18:26:58Z
Severity
  • 7.1 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H CVSS Calculator
Summary
crypto: ccp: Don't attempt to copy PDH cert to userspace if PSP command failed
Details

In the Linux kernel, the following vulnerability has been resolved:

crypto: ccp: Don't attempt to copy PDH cert to userspace if PSP command failed

When retrieving the PDH cert, don't attempt to copy the blobs 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 2084 at addr ffff8885c4ab8aa0 by task syz.0.186/21033

CPU: 51 UID: 0 PID: 21033 Comm: syz.0.186 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 34.84.12-0 11/17/2025 Call Trace: 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_pdh_export+0x3d3/0x7c0 ../drivers/crypto/ccp/sev-dev.c:2347 sev_ioctl+0x2a2/0x490 ../drivers/crypto/ccp/sev-dev.c:2568 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

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.

Database specific
{
    "cna_assigner":  "Linux",
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31698.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
76a2b524a4b1d6dc0f2421f9854a01d55d5e5436
Fixed
af67d35da744b6b678c7a0296d9c679658779829
Fixed
854d7846e1d29f32f1bbeb2e869e794df12067f6
Fixed
25d9b3446001185484209cf57951f3368462b631
Fixed
b5c14bd4da1f376f385722fe1da993f1edab6472
Fixed
78b97e43d0b3e674d9d49ae56937b11e2ba3fcaf
Fixed
051e51aa55fd4cdc3e8283cf4476aeeb5f563274
Fixed
50808c13452dae43a2c90b1bbbf9daa16501ce70
Fixed
e76239fed3cffd6d304d8ca3ce23984fd24f57d3

Database specific

source
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31698.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
4.16.0
Fixed
5.10.258
Type
ECOSYSTEM
Events
Introduced
5.11.0
Fixed
5.15.209
Type
ECOSYSTEM
Events
Introduced
5.16.0
Fixed
6.1.175
Type
ECOSYSTEM
Events
Introduced
6.2.0
Fixed
6.6.136
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.12.84
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
6.18.25
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.0.2

Database specific

source
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31698.json"