GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2025-38404 (GCVE-0-2025-38404)

Vulnerability from cvelistv5 – Published: 2025-07-25 13:09 – Updated: 2026-05-11 21:27
VLAI
Title
usb: typec: displayport: Fix potential deadlock
Summary
In the Linux kernel, the following vulnerability has been resolved: usb: typec: displayport: Fix potential deadlock The deadlock can occur due to a recursive lock acquisition of `cros_typec_altmode_data::mutex`. The call chain is as follows: 1. cros_typec_altmode_work() acquires the mutex 2. typec_altmode_vdm() -> dp_altmode_vdm() -> 3. typec_altmode_exit() -> cros_typec_altmode_exit() 4. cros_typec_altmode_exit() attempts to acquire the mutex again To prevent this, defer the `typec_altmode_exit()` call by scheduling it rather than calling it directly from within the mutex-protected context.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e0359c66c1beccbe90119a63391678eabda38007 , < 749d9076735fb497aae60fbea9fff563f9ea3254 (git)
Affected: e3fb6c2c3939b4aad203cacdd613a62ce1fd032c , < eb08fca56f1f39e4038cb9bac9864464b13b00aa (git)
Affected: 56846793f105cf2b39ecbde4f3ae86342091f6fc , < 7be0d1ea71f52595499da39cea484a895e8ed042 (git)
Affected: 8e8a69b1f8c59f0505f8a1c0fb77191f27b75011 , < 76cf1f33e7319fe74c94ac92f9814094ee8cc84b (git)
Affected: 8851e40587013db00b71d4aeaae30f5fd59b0eec , < 63cff9f57e86b2dc25d7487ca0118df89a665296 (git)
Affected: 10cc2cfd3e5d0e0ec7590c4bee8bcea10e5492c4 , < c782f98eef14197affa8a7b91e6981420f109ea9 (git)
Affected: 8f6a4fa7b663468bb304cb885b93326e025ae005 , < 80c25d7916a44715338d4f8924c8e52af50d0b9f (git)
Affected: b4b38ffb38c91afd4dc387608db26f6fc34ed40b , < 099cf1fbb8afc3771f408109f62bdec66f85160e (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.1.143 , < 6.1.144 (semver)
Affected: 6.6.96 , < 6.6.97 (semver)
Affected: 6.12.36 , < 6.12.37 (semver)
Affected: 6.15.5 , < 6.15.6 (semver)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-03T17:37:39.276Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
          },
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/typec/altmodes/displayport.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "749d9076735fb497aae60fbea9fff563f9ea3254",
              "status": "affected",
              "version": "e0359c66c1beccbe90119a63391678eabda38007",
              "versionType": "git"
            },
            {
              "lessThan": "eb08fca56f1f39e4038cb9bac9864464b13b00aa",
              "status": "affected",
              "version": "e3fb6c2c3939b4aad203cacdd613a62ce1fd032c",
              "versionType": "git"
            },
            {
              "lessThan": "7be0d1ea71f52595499da39cea484a895e8ed042",
              "status": "affected",
              "version": "56846793f105cf2b39ecbde4f3ae86342091f6fc",
              "versionType": "git"
            },
            {
              "lessThan": "76cf1f33e7319fe74c94ac92f9814094ee8cc84b",
              "status": "affected",
              "version": "8e8a69b1f8c59f0505f8a1c0fb77191f27b75011",
              "versionType": "git"
            },
            {
              "lessThan": "63cff9f57e86b2dc25d7487ca0118df89a665296",
              "status": "affected",
              "version": "8851e40587013db00b71d4aeaae30f5fd59b0eec",
              "versionType": "git"
            },
            {
              "lessThan": "c782f98eef14197affa8a7b91e6981420f109ea9",
              "status": "affected",
              "version": "10cc2cfd3e5d0e0ec7590c4bee8bcea10e5492c4",
              "versionType": "git"
            },
            {
              "lessThan": "80c25d7916a44715338d4f8924c8e52af50d0b9f",
              "status": "affected",
              "version": "8f6a4fa7b663468bb304cb885b93326e025ae005",
              "versionType": "git"
            },
            {
              "lessThan": "099cf1fbb8afc3771f408109f62bdec66f85160e",
              "status": "affected",
              "version": "b4b38ffb38c91afd4dc387608db26f6fc34ed40b",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/typec/altmodes/displayport.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "6.1.144",
              "status": "affected",
              "version": "6.1.143",
              "versionType": "semver"
            },
            {
              "lessThan": "6.6.97",
              "status": "affected",
              "version": "6.6.96",
              "versionType": "semver"
            },
            {
              "lessThan": "6.12.37",
              "status": "affected",
              "version": "6.12.36",
              "versionType": "semver"
            },
            {
              "lessThan": "6.15.6",
              "status": "affected",
              "version": "6.15.5",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.144",
                  "versionStartIncluding": "6.1.143",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.97",
                  "versionStartIncluding": "6.6.96",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.37",
                  "versionStartIncluding": "6.12.36",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.15.6",
                  "versionStartIncluding": "6.15.5",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: typec: displayport: Fix potential deadlock\n\nThe deadlock can occur due to a recursive lock acquisition of\n`cros_typec_altmode_data::mutex`.\nThe call chain is as follows:\n1. cros_typec_altmode_work() acquires the mutex\n2. typec_altmode_vdm() -\u003e dp_altmode_vdm() -\u003e\n3. typec_altmode_exit() -\u003e cros_typec_altmode_exit()\n4. cros_typec_altmode_exit() attempts to acquire the mutex again\n\nTo prevent this, defer the `typec_altmode_exit()` call by scheduling\nit rather than calling it directly from within the mutex-protected\ncontext."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T21:27:19.855Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/749d9076735fb497aae60fbea9fff563f9ea3254"
        },
        {
          "url": "https://git.kernel.org/stable/c/eb08fca56f1f39e4038cb9bac9864464b13b00aa"
        },
        {
          "url": "https://git.kernel.org/stable/c/7be0d1ea71f52595499da39cea484a895e8ed042"
        },
        {
          "url": "https://git.kernel.org/stable/c/76cf1f33e7319fe74c94ac92f9814094ee8cc84b"
        },
        {
          "url": "https://git.kernel.org/stable/c/63cff9f57e86b2dc25d7487ca0118df89a665296"
        },
        {
          "url": "https://git.kernel.org/stable/c/c782f98eef14197affa8a7b91e6981420f109ea9"
        },
        {
          "url": "https://git.kernel.org/stable/c/80c25d7916a44715338d4f8924c8e52af50d0b9f"
        },
        {
          "url": "https://git.kernel.org/stable/c/099cf1fbb8afc3771f408109f62bdec66f85160e"
        }
      ],
      "title": "usb: typec: displayport: Fix potential deadlock",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-38404",
    "datePublished": "2025-07-25T13:09:25.822Z",
    "dateReserved": "2025-04-16T04:51:24.012Z",
    "dateUpdated": "2026-05-11T21:27:19.855Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-38404",
      "date": "2026-09-19",
      "epss": "0.00132",
      "percentile": "0.03174"
    },
    "microsoft_vex": {
      "current_release_date": "2025-09-04T04:49:40.000Z",
      "cve": "CVE-2025-38404",
      "id": "msrc_CVE-2025-38404",
      "initial_release_date": "2025-07-02T00:00:00.000Z",
      "product_status:fixed": "1",
      "product_status:known_affected": "2",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "usb: typec: displayport: Fix potential deadlock",
      "url": "https://msrc.microsoft.com/csaf/vex/2025/msrc_cve-2025-38404.json",
      "version": "1"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "drivers/usb/typec/altmodes/displayport.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "749d9076735fb497aae60fbea9fff563f9ea3254",
                    "status": "affected",
                    "version": "e0359c66c1beccbe90119a63391678eabda38007",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "eb08fca56f1f39e4038cb9bac9864464b13b00aa",
                    "status": "affected",
                    "version": "e3fb6c2c3939b4aad203cacdd613a62ce1fd032c",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "7be0d1ea71f52595499da39cea484a895e8ed042",
                    "status": "affected",
                    "version": "56846793f105cf2b39ecbde4f3ae86342091f6fc",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "76cf1f33e7319fe74c94ac92f9814094ee8cc84b",
                    "status": "affected",
                    "version": "8e8a69b1f8c59f0505f8a1c0fb77191f27b75011",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "63cff9f57e86b2dc25d7487ca0118df89a665296",
                    "status": "affected",
                    "version": "8851e40587013db00b71d4aeaae30f5fd59b0eec",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "c782f98eef14197affa8a7b91e6981420f109ea9",
                    "status": "affected",
                    "version": "10cc2cfd3e5d0e0ec7590c4bee8bcea10e5492c4",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "80c25d7916a44715338d4f8924c8e52af50d0b9f",
                    "status": "affected",
                    "version": "8f6a4fa7b663468bb304cb885b93326e025ae005",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "099cf1fbb8afc3771f408109f62bdec66f85160e",
                    "status": "affected",
                    "version": "b4b38ffb38c91afd4dc387608db26f6fc34ed40b",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "drivers/usb/typec/altmodes/displayport.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "6.1.144",
                    "status": "affected",
                    "version": "6.1.143",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.6.97",
                    "status": "affected",
                    "version": "6.6.96",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.12.37",
                    "status": "affected",
                    "version": "6.12.36",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.15.6",
                    "status": "affected",
                    "version": "6.15.5",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.1.143:*:*:*:*:*:*:*",
                    "matchCriteriaId": "BC911939-54F8-4A96-9EAD-B332B4105848",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.6.96:*:*:*:*:*:*:*",
                    "matchCriteriaId": "D4BFAA60-0B04-414F-8687-99789216F0F2",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.12.36:*:*:*:*:*:*:*",
                    "matchCriteriaId": "6822DD31-0F5F-45F9-BF68-F5D92B0C5A6F",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.15.5:*:*:*:*:*:*:*",
                    "matchCriteriaId": "3C9A4EA6-40DD-44AC-AEDD-0246F4590C75",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "6D4894DB-CCFE-4602-B1BF-3960B2E19A01",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "09709862-E348-4378-8632-5A7813EDDC86",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "415BF58A-8197-43F5-B3D7-D1D63057A26E",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:*",
                    "matchCriteriaId": "A0517869-312D-4429-80C2-561086E1421C",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          },
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
                    "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: typec: displayport: Fix potential deadlock\n\nThe deadlock can occur due to a recursive lock acquisition of\n`cros_typec_altmode_data::mutex`.\nThe call chain is as follows:\n1. cros_typec_altmode_work() acquires the mutex\n2. typec_altmode_vdm() -\u003e dp_altmode_vdm() -\u003e\n3. typec_altmode_exit() -\u003e cros_typec_altmode_exit()\n4. cros_typec_altmode_exit() attempts to acquire the mutex again\n\nTo prevent this, defer the `typec_altmode_exit()` call by scheduling\nit rather than calling it directly from within the mutex-protected\ncontext."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: usb: typec: displayport: Soluciona un posible bloqueo El bloqueo puede ocurrir debido a una adquisici\u00f3n de bloqueo recursiva de `cros_typec_altmode_data::mutex`. La cadena de llamadas es la siguiente: 1. cros_typec_altmode_work() adquiere el mutex 2. typec_altmode_vdm() -\u0026gt; dp_altmode_vdm() -\u0026gt; 3. typec_altmode_exit() -\u0026gt; cros_typec_altmode_exit() 4. cros_typec_altmode_exit() intenta adquirir el mutex de nuevo Para evitar esto, aplaza la llamada a `typec_altmode_exit()` program\u00e1ndola en lugar de llamarla directamente desde dentro del contexto protegido por mutex."
          }
        ],
        "id": "CVE-2025-38404",
        "lastModified": "2026-06-17T09:16:47.617",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2025-07-25T14:15:31.950",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/099cf1fbb8afc3771f408109f62bdec66f85160e"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/63cff9f57e86b2dc25d7487ca0118df89a665296"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/749d9076735fb497aae60fbea9fff563f9ea3254"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/76cf1f33e7319fe74c94ac92f9814094ee8cc84b"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/7be0d1ea71f52595499da39cea484a895e8ed042"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/80c25d7916a44715338d4f8924c8e52af50d0b9f"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/c782f98eef14197affa8a7b91e6981420f109ea9"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/eb08fca56f1f39e4038cb9bac9864464b13b00aa"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Third Party Advisory"
            ],
            "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Third Party Advisory"
            ],
            "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-667"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "None",
      "current_release_date": "2026-06-30T10:17:23+00:00",
      "cve": "CVE-2025-38404",
      "id": "CVE-2025-38404",
      "initial_release_date": "2025-07-25T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: usb: typec: displayport: Fix potential deadlock",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38404.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-31T13:48:13Z",
      "cve": "CVE-2025-38404",
      "id": "CVE-2025-38404",
      "initial_release_date": "2025-07-29T23:23:59Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "394",
      "product_status:known_not_affected": "442",
      "product_status:recommended": "472",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-38404",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-38404.json",
      "version": "47"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


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.