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CVE-2026-31698

Full vulnerability record from the local CVENow database.

Description

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: <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_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 </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.

Severity
HIGH
CVSS score
7.1 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-01 14:16:19.650000
Last modified
2026-10-19 20:17:56.097000
View original CVE JSON
{
  "id": "CVE-2026-31698",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-01T14:16:19.650",
  "lastModified": "2026-10-19T20:17:56.097",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp: Don't attempt to copy PDH cert to userspace if PSP command failed\n\nWhen retrieving the PDH cert, don't attempt to copy the blobs to userspace\nif the firmware command failed.  If the failure was due to an invalid\nlength, i.e. the userspace buffer+length was too small, copying the number\nof bytes _firmware_ requires will overflow the kernel-allocated buffer and\nleak data to userspace.\n\n  BUG: KASAN: slab-out-of-bounds in instrument_copy_to_user ../include/linux/instrumented.h:129 [inline]\n  BUG: KASAN: slab-out-of-bounds in _inline_copy_to_user ../include/linux/uaccess.h:205 [inline]\n  BUG: KASAN: slab-out-of-bounds in _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26\n  Read of size 2084 at addr ffff8885c4ab8aa0 by task syz.0.186/21033\n\n  CPU: 51 UID: 0 PID: 21033 Comm: syz.0.186 Tainted: G     U     O        7.0.0-smp-DEV #28 PREEMPTLAZY\n  Tainted: [U]=USER, [O]=OOT_MODULE\n  Hardware name: Google, Inc.                                                       Arcadia_IT_80/Arcadia_IT_80, BIOS 34.84.12-0 11/17/2025\n  Call Trace:\n   <TASK>\n   dump_stack_lvl+0xc5/0x110 ../lib/dump_stack.c:120\n   print_address_description ../mm/kasan/report.c:378 [inline]\n   print_report+0xbc/0x260 ../mm/kasan/report.c:482\n   kasan_report+0xa2/0xe0 ../mm/kasan/report.c:595\n   check_region_inline ../mm/kasan/generic.c:-1 [inline]\n   kasan_check_range+0x264/0x2c0 ../mm/kasan/generic.c:200\n   instrument_copy_to_user ../include/linux/instrumented.h:129 [inline]\n   _inline_copy_to_user ../include/linux/uaccess.h:205 [inline]\n   _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26\n   copy_to_user ../include/linux/uaccess.h:236 [inline]\n   sev_ioctl_do_pdh_export+0x3d3/0x7c0 ../drivers/crypto/ccp/sev-dev.c:2347\n   sev_ioctl+0x2a2/0x490 ../drivers/crypto/ccp/sev-dev.c:2568\n   vfs_ioctl ../fs/ioctl.c:51 [inline]\n   __do_sys_ioctl ../fs/ioctl.c:597 [inline]\n   __se_sys_ioctl+0x11d/0x1b0 ../fs/ioctl.c:583\n   do_syscall_x64 ../arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0xe0/0x800 ../arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x76/0x7e\n   </TASK>\n\nWARN if the driver says the command succeeded, but the firmware error code\nsays otherwise, as __sev_do_cmd_locked() is expected to return -EIO on any\nfirwmware error."
    }
  ],
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              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
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      "affectedData": [
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          "vendor": "Siemens",
          "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
          "defaultStatus": "unknown",
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              "lessThan": "*",
              "versionType": "custom",
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  "metrics": {
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        "type": "Secondary",
        "cvssData": {
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.2
      }
    ],
    "ssvcV203": [
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
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          "id": "CVE-2026-31698",
          "options": [
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            },
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            },
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          "role": "CISA Coordinator",
          "version": "2.0.3"
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  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
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          "value": "CWE-787"
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          "value": "CWE-125"
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          "negate": false,
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