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

CVE-2026-89480 (GCVE-0-2026-89480)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:43 – Updated: 2026-09-14 12:00
VLAI
Title
nvme-tcp: reject a read that transferred too few bytes
Summary
In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: reject a read that transferred too few bytes nvme_tcp_recv_data() completes a request once the current C2HData PDU has been consumed. Nothing compares the total bytes received against the length the command asked for: struct nvme_tcp_request has no receive-side counter, queue->data_remaining is per queue, and blk_mq_end_request() completes for blk_rq_bytes(rq) unconditionally with no residual concept anywhere above. A controller can therefore answer a 4096-byte read with 512 bytes and have it reported as a complete read; user space then gets 4096 bytes of which 3584 are whatever was already in the page. I reproduced that with a test target. Count the bytes received and refuse to complete a successful read whose count does not match, at the two NVME_TCP_F_DATA_SUCCESS paths and in nvme_tcp_process_nvme_cqe(). The success test shifts req->status right by one, because the driver keeps the wire value there and shifts it on completion, so the check must see what the completion path will see. Only REQ_OP_READ is checked, because there the length comes from the sectors the request covers; a passthrough command is built by its submitter, which picks both command and buffer, so the kernel has nothing to compare against.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < a5c1bb0fb1bab2f24a081339c145870697f6d220 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < aa107e3a68f4af177d60f2d87679e7f67179a36c (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < fca3ebb63e5c82561cd9934365dcc0d068008006 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 99066cf9bba175f610ceb61a35f6fc9fbc33ff65 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 8a02ad98798fd01f51f648c1fdd8f3c9d07195d3 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 832a685efeb5d925ee7d30011d2dbe45f81447a3 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.0
Unaffected: 0 , < 5.0 (semver)
Unaffected: 5.15.221 , ≤ 5.15.* (semver)
Unaffected: 6.1.188 , ≤ 6.1.* (semver)
Unaffected: 6.6.157 , ≤ 6.6.* (semver)
Unaffected: 6.12.109 , ≤ 6.12.* (semver)
Unaffected: 6.18.50 , ≤ 6.18.* (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/nvme/host/tcp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "a5c1bb0fb1bab2f24a081339c145870697f6d220",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            },
            {
              "lessThan": "aa107e3a68f4af177d60f2d87679e7f67179a36c",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            },
            {
              "lessThan": "fca3ebb63e5c82561cd9934365dcc0d068008006",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            },
            {
              "lessThan": "99066cf9bba175f610ceb61a35f6fc9fbc33ff65",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            },
            {
              "lessThan": "8a02ad98798fd01f51f648c1fdd8f3c9d07195d3",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            },
            {
              "lessThan": "832a685efeb5d925ee7d30011d2dbe45f81447a3",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            },
            {
              "lessThan": "7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12",
              "status": "affected",
              "version": "3f2304f8c6d6ed97849057bd16fee99e434ca796",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/nvme/host/tcp.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.0"
            },
            {
              "lessThan": "5.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.221",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.188",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.157",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.109",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.50",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "5.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-tcp: reject a read that transferred too few bytes\n\nnvme_tcp_recv_data() completes a request once the current C2HData PDU\nhas been consumed. Nothing compares the total bytes received against\nthe length the command asked for: struct nvme_tcp_request has no\nreceive-side counter, queue-\u003edata_remaining is per queue, and\nblk_mq_end_request() completes for blk_rq_bytes(rq) unconditionally\nwith no residual concept anywhere above.\n\nA controller can therefore answer a 4096-byte read with 512 bytes and\nhave it reported as a complete read; user space then gets 4096 bytes of\nwhich 3584 are whatever was already in the page. I reproduced that with\na test target.\n\nCount the bytes received and refuse to complete a successful read whose\ncount does not match, at the two NVME_TCP_F_DATA_SUCCESS paths and in\nnvme_tcp_process_nvme_cqe(). The success test shifts req-\u003estatus right\nby one, because the driver keeps the wire value there and shifts it on\ncompletion, so the check must see what the completion path will see.\nOnly REQ_OP_READ is checked, because there the length comes from the\nsectors the request covers; a passthrough command is built by its\nsubmitter, which picks both command and buffer, so the kernel has\nnothing to compare against."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - C2HData is parsed on the nvme-tcp host socket path (nvme_tcp_data_ready -\u003e nvme_tcp_try_recv -\u003e nvme_tcp_recv_skb -\u003e nvme_tcp_recv_data) over routable TCP (typically 4420). A malicious or compromised NVMe-oF target, or an on-path injector into the default-unencrypted stream, triggers it from the network.\nAC:L - nvme_tcp_handle_c2h_data() sets queue-\u003edata_remaining from the attacker-controlled PDU data_length with no comparison to req-\u003edata_len. A short or zero-length C2HData with NVME_TCP_F_DATA_SUCCESS, or a short C2HData plus a success CQE, completes the read every time; no race or layout dependence.\nPR:N - The attacker is the NVMe-oF peer and needs no host account or capability. NVMe/TCP is unauthenticated by default (DH-HMAC-CHAP and TLS are optional), so a malicious, compromised, or spoofed target can short any in-flight read once the fabrics connection exists.\nUI:N - NVMe-oF controllers are persistent boot/autoconnect configuration and are re-established by nvme_tcp_error_recovery(). Namespace scan, partition probe, udev, and mounted-filesystem readahead issue REQ_OP_READ from kernel work without further victim action at attack time.\nS:U - Leftover host page-cache and buddy-page contents are exposed to local readers of the same kernel\u0027s NVMe device. No VM, IOMMU, or sandbox boundary is crossed.\nC:H - blk_mq_end_request() completes the full blk_rq_bytes, so userspace and page cache see leftover destination-page bytes as valid data. Those pages are not zeroed; sibling CVE-2026-89481 showed they hold stale kernel data including struct page pointers. Leak size is attacker-chosen up to the whole I/O, including a 0-length SUCCESS PDU.\nI:N - The bug under-fills the bio and reports success; it does not write out of bounds, free an object, or give a kernel write/hijack primitive. Bytes the target does send are data a storage controller already controls, and leftover bytes are prior page contents rather than attacker-chosen writes.\nA:N - The vulnerable path completes the request as success with no oops, panic, hang, deadlock, or leak. Availability of the host kernel is unaffected; error recovery (-EPROTO) exists only after the fix."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-14T12:00:17.079Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/a5c1bb0fb1bab2f24a081339c145870697f6d220"
        },
        {
          "url": "https://git.kernel.org/stable/c/aa107e3a68f4af177d60f2d87679e7f67179a36c"
        },
        {
          "url": "https://git.kernel.org/stable/c/fca3ebb63e5c82561cd9934365dcc0d068008006"
        },
        {
          "url": "https://git.kernel.org/stable/c/99066cf9bba175f610ceb61a35f6fc9fbc33ff65"
        },
        {
          "url": "https://git.kernel.org/stable/c/8a02ad98798fd01f51f648c1fdd8f3c9d07195d3"
        },
        {
          "url": "https://git.kernel.org/stable/c/832a685efeb5d925ee7d30011d2dbe45f81447a3"
        },
        {
          "url": "https://git.kernel.org/stable/c/7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12"
        }
      ],
      "title": "nvme-tcp: reject a read that transferred too few bytes",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89480",
    "datePublished": "2026-09-11T19:43:35.930Z",
    "dateReserved": "2026-09-11T19:38:34.711Z",
    "dateUpdated": "2026-09-14T12:00:17.079Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-89480",
      "date": "2026-09-15",
      "epss": "0.00415",
      "percentile": "0.35063"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-89480\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-09-11T20:19:29.470\",\"lastModified\":\"2026-09-14T13:19:04.623\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnvme-tcp: reject a read that transferred too few bytes\\n\\nnvme_tcp_recv_data() completes a request once the current C2HData PDU\\nhas been consumed. Nothing compares the total bytes received against\\nthe length the command asked for: struct nvme_tcp_request has no\\nreceive-side counter, queue-\u003edata_remaining is per queue, and\\nblk_mq_end_request() completes for blk_rq_bytes(rq) unconditionally\\nwith no residual concept anywhere above.\\n\\nA controller can therefore answer a 4096-byte read with 512 bytes and\\nhave it reported as a complete read; user space then gets 4096 bytes of\\nwhich 3584 are whatever was already in the page. I reproduced that with\\na test target.\\n\\nCount the bytes received and refuse to complete a successful read whose\\ncount does not match, at the two NVME_TCP_F_DATA_SUCCESS paths and in\\nnvme_tcp_process_nvme_cqe(). The success test shifts req-\u003estatus right\\nby one, because the driver keeps the wire value there and shifts it on\\ncompletion, so the check must see what the completion path will see.\\nOnly REQ_OP_READ is checked, because there the length comes from the\\nsectors the request covers; a passthrough command is built by its\\nsubmitter, which picks both command and buffer, so the kernel has\\nnothing to compare against.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/nvme/host/tcp.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"a5c1bb0fb1bab2f24a081339c145870697f6d220\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"aa107e3a68f4af177d60f2d87679e7f67179a36c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"fca3ebb63e5c82561cd9934365dcc0d068008006\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"99066cf9bba175f610ceb61a35f6fc9fbc33ff65\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"8a02ad98798fd01f51f648c1fdd8f3c9d07195d3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"832a685efeb5d925ee7d30011d2dbe45f81447a3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3f2304f8c6d6ed97849057bd16fee99e434ca796\",\"lessThan\":\"7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/nvme/host/tcp.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.0\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.0\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.221\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.188\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.157\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.109\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.50\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2.4\",\"lessThanOrEqual\":\"7.2.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.3-rc1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/7fa3f73f6c8ddc5f0425b50fb2a626a782ef7d12\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/832a685efeb5d925ee7d30011d2dbe45f81447a3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8a02ad98798fd01f51f648c1fdd8f3c9d07195d3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/99066cf9bba175f610ceb61a35f6fc9fbc33ff65\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a5c1bb0fb1bab2f24a081339c145870697f6d220\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/aa107e3a68f4af177d60f2d87679e7f67179a36c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/fca3ebb63e5c82561cd9934365dcc0d068008006\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-13T06:56:04+00:00",
      "cve": "CVE-2026-89480",
      "id": "CVE-2026-89480",
      "initial_release_date": "2026-09-11T19:43:35.930000+00:00",
      "product_status:known_affected": "2",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel: NVMe-TCP vulnerability allows information disclosure due to incomplete data transfer",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89480.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "low",
      "current_release_date": "2026-09-16T00:03:09Z",
      "cve": "CVE-2026-89480",
      "id": "CVE-2026-89480",
      "initial_release_date": "2026-09-12T16:27:47Z",
      "product_status:known_affected": "293",
      "product_status:known_not_affected": "60",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-89480",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-89480.json",
      "version": "3"
    }
  }
}



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.