Vulnerability-Lookup

BDU:2023-00744 (CVE-2022-20568)

Vulnerability from fstec – Published: 2023-02-15 – Updated: 2024-05-16 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции io_statx() в модуле fs/io_uring.c компонента io_uring ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании или повысить привилегии

Summary

Уязвимость функции io_statx() в модуле fs/io_uring.c компонента io_uring ядра операционной системы Linux связана с использованием ранее освобожденной памяти. Эксплуатация уязвимости может позволить нарушителю вызвать отказ в обслуживании или повысить свои привилегии

Severity

6.8 (Medium) CVSS 2.0


                      
                        AV:L/AC:L/Au:S/C:C/I:C/A:C

7.8 (High) CVSS 3.0


                      
                        CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-416 - Использование после освобождения

Aliases

CVE-2022-20568

References

8 references

URL
https://android.googlesource.com/kernel/common/+/bc80ea8a4296c4d75f7e3e27b65718…
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-20568
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/fs/io_u…
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.118
https://lore.kernel.org/io-uring/YoOJ%2FT4QRKC+fAZE@google.com
https://lore.kernel.org/io-uring/YoOJ%2FT4QRKC+fAZE@google.com/
https://source.android.com/docs/security/bulletin/pixel/2022-12-01
https://www.cve.org/CVERecord?id=CVE-2022-20568

Impacted products

2 products from 2 vendors

Vendors

Google Inc, Сообщество свободного программного обеспечения

Products

Android, Linux

Versions

- (Android), 5.11 (Linux), от 5.6.11 до 5.10.117 включительно (Linux)

Product types

Operating system

Platforms

Google Inc Android -, Сообщество свободного программного обеспечения Linux 5.11, Сообщество свободного программного обеспечения Linux от 5.6.11 до 5.10.117 включительно

Mitigations

Использование рекомендаций: Для Linux: https://lore.kernel.org/io-uring/YoOJ%2FT4QRKC+fAZE@google.com https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/fs/io_uring.c?h=linux-5.10.y&id=3c48558be571e01f67e65edcf03193484eeb2b79 https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.118 Для Android: https://source.android.com/security/bulletin/pixel/2022-12-01

JSON

To clipboard

{
  "CVSS 2.0": "AV:L/AC:L/Au:S/C:C/I:C/A:C",
  "CVSS 3.0": "AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Google Inc, \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "- (Android), 5.11 (Linux), \u043e\u0442 5.6.11 \u0434\u043e 5.10.117 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\n\u0414\u043b\u044f Linux:\nhttps://lore.kernel.org/io-uring/YoOJ%2FT4QRKC+fAZE@google.com\nhttps://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/fs/io_uring.c?h=linux-5.10.y\u0026id=3c48558be571e01f67e65edcf03193484eeb2b79\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.118\n\n\u0414\u043b\u044f Android:\nhttps://source.android.com/security/bulletin/pixel/2022-12-01",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "25.05.2022",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "16.05.2024",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "15.02.2023",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2023-00744",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2022-20568",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Android, Linux",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": "Google Inc Android - , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux 5.11 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.6.11 \u0434\u043e 5.10.117 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e ",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 io_statx() \u0432 \u043c\u043e\u0434\u0443\u043b\u0435 fs/io_uring.c \u043a\u043e\u043c\u043f\u043e\u043d\u0435\u043d\u0442\u0430 io_uring \u044f\u0434\u0440\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Linux, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438 \u0438\u043b\u0438 \u043f\u043e\u0432\u044b\u0441\u0438\u0442\u044c \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u043f\u043e\u0441\u043b\u0435 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u044f (CWE-416)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 io_statx() \u0432 \u043c\u043e\u0434\u0443\u043b\u0435 fs/io_uring.c \u043a\u043e\u043c\u043f\u043e\u043d\u0435\u043d\u0442\u0430 io_uring \u044f\u0434\u0440\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Linux \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435\u043c \u0440\u0430\u043d\u0435\u0435 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u043d\u043e\u0439 \u043f\u0430\u043c\u044f\u0442\u0438. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438 \u0438\u043b\u0438 \u043f\u043e\u0432\u044b\u0441\u0438\u0442\u044c \u0441\u0432\u043e\u0438 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u0430\u043c\u0438 \u0434\u0430\u043d\u043d\u044b\u0445",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://android.googlesource.com/kernel/common/+/bc80ea8a4296c4d75f7e3e27b65718cae09f20f1\nhttps://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-20568\nhttps://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/fs/io_uring.c?h=linux-5.10.y\u0026id=3c48558be571e01f67e65edcf03193484eeb2b79\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.118\nhttps://lore.kernel.org/io-uring/YoOJ%2FT4QRKC+fAZE@google.com\nhttps://lore.kernel.org/io-uring/YoOJ%2FT4QRKC+fAZE@google.com/\nhttps://source.android.com/docs/security/bulletin/pixel/2022-12-01\nhttps://www.cve.org/CVERecord?id=CVE-2022-20568",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u0430\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u0430",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-416",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 6,8)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,8)"
}

CVE-2022-20568 (GCVE-0-2022-20568)

Vulnerability from cvelistv5 – Published: 2022-12-16 00:00 – Updated: 2025-04-21 13:00

Summary

In (TBD) of (TBD), there is a possible way to corrupt kernel memory due to a use after free. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-220738351References: Upstream kernel

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-04-21 12:59 UTC

CWE

Elevation of privilege
CWE-416 - Use After Free

Assigner

google_android Google root

References

1 reference

URL	Tags
https://source.android.com/security/bulletin/pixe…

Impacted products

1 product

Vendor	Product	Version
n/a	Android	Affected: Android kernel

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T02:17:52.910Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://source.android.com/security/bulletin/pixel/2022-12-01"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 7.8,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2022-20568",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-04-21T12:59:57.297038Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-416",
                "description": "CWE-416 Use After Free",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-04-21T13:00:17.375Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Android",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "Android kernel"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In (TBD) of (TBD), there is a possible way to corrupt kernel memory due to a use after free. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-220738351References: Upstream kernel"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "Elevation of privilege",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2022-12-16T00:00:00.000Z",
        "orgId": "baff130e-b8d5-4e15-b3d3-c3cf5d5545c6",
        "shortName": "google_android"
      },
      "references": [
        {
          "url": "https://source.android.com/security/bulletin/pixel/2022-12-01"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "baff130e-b8d5-4e15-b3d3-c3cf5d5545c6",
    "assignerShortName": "google_android",
    "cveId": "CVE-2022-20568",
    "datePublished": "2022-12-16T00:00:00.000Z",
    "dateReserved": "2021-10-14T00:00:00.000Z",
    "dateUpdated": "2025-04-21T13:00:17.375Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.