CVE-2026-74557 (GCVE-0-2026-74557)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:28 – Updated: 2026-08-17 05:48
VLAI
Title
scsi: libiscsi: Fix stale-data leak into the SCSI sense buffer
Summary
In the Linux kernel, the following vulnerability has been resolved: scsi: libiscsi: Fix stale-data leak into the SCSI sense buffer iscsi_scsi_cmd_rsp() copies the sense data of a SCSI Response from the target-supplied data segment. The segment carries a 2-byte sense length followed by the sense bytes, so it must hold 2 + senselen bytes, but the bounds check only requires datalen >= senselen: senselen = get_unaligned_be16(data); if (datalen < senselen) goto invalid_datalen; memcpy(sc->sense_buffer, data + 2, min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE)); A target that returns a SCSI Response whose datalen equals senselen (with senselen <= SCSI_SENSE_BUFFERSIZE) makes the memcpy() from data + 2 read up to two bytes past the received data. Those bytes are stale conn->data contents and end up in the command's sense buffer, which is returned to userspace. Account for the 2-byte sense length prefix in the check.
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: 7996a778ff8c717cb1a7a294475c59cc8f1e9fb8 , < 7567f06abdefb1caf2d836107c4d08c5185c650e (git)
Affected: 7996a778ff8c717cb1a7a294475c59cc8f1e9fb8 , < 60499924faf4ef97e84228c20515218ef121facf (git)
Affected: 7996a778ff8c717cb1a7a294475c59cc8f1e9fb8 , < 3ef209ca0b4b68c75e9a814d90cc916026b5a6ac (git)
Affected: 7996a778ff8c717cb1a7a294475c59cc8f1e9fb8 , < 1f07a897d43c63e6c9458bf77450defef39b5833 (git)
Affected: 7996a778ff8c717cb1a7a294475c59cc8f1e9fb8 , < 98b87885de4b7f605533a2860685f5689fce8e82 (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.18
Unaffected: 0 , < 2.6.18 (semver)
Unaffected: 6.6.151 , ≤ 6.6.* (semver)
Unaffected: 6.12.103 , ≤ 6.12.* (semver)
Unaffected: 6.18.44 , ≤ 6.18.* (semver)
Unaffected: 7.1.8 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (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/scsi/libiscsi.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7567f06abdefb1caf2d836107c4d08c5185c650e",
              "status": "affected",
              "version": "7996a778ff8c717cb1a7a294475c59cc8f1e9fb8",
              "versionType": "git"
            },
            {
              "lessThan": "60499924faf4ef97e84228c20515218ef121facf",
              "status": "affected",
              "version": "7996a778ff8c717cb1a7a294475c59cc8f1e9fb8",
              "versionType": "git"
            },
            {
              "lessThan": "3ef209ca0b4b68c75e9a814d90cc916026b5a6ac",
              "status": "affected",
              "version": "7996a778ff8c717cb1a7a294475c59cc8f1e9fb8",
              "versionType": "git"
            },
            {
              "lessThan": "1f07a897d43c63e6c9458bf77450defef39b5833",
              "status": "affected",
              "version": "7996a778ff8c717cb1a7a294475c59cc8f1e9fb8",
              "versionType": "git"
            },
            {
              "lessThan": "98b87885de4b7f605533a2860685f5689fce8e82",
              "status": "affected",
              "version": "7996a778ff8c717cb1a7a294475c59cc8f1e9fb8",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/scsi/libiscsi.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.18"
            },
            {
              "lessThan": "2.6.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.151",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.103",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.44",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.151",
                  "versionStartIncluding": "2.6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.103",
                  "versionStartIncluding": "2.6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.44",
                  "versionStartIncluding": "2.6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.8",
                  "versionStartIncluding": "2.6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "2.6.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: libiscsi: Fix stale-data leak into the SCSI sense buffer\n\niscsi_scsi_cmd_rsp() copies the sense data of a SCSI Response from the\ntarget-supplied data segment.  The segment carries a 2-byte sense length\nfollowed by the sense bytes, so it must hold 2 + senselen bytes, but the\nbounds check only requires datalen \u003e= senselen:\n\n\tsenselen = get_unaligned_be16(data);\n\tif (datalen \u003c senselen)\n\t\tgoto invalid_datalen;\n\tmemcpy(sc-\u003esense_buffer, data + 2,\n\t       min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));\n\nA target that returns a SCSI Response whose datalen equals senselen\n(with senselen \u003c= SCSI_SENSE_BUFFERSIZE) makes the memcpy() from data +\n2 read up to two bytes past the received data.  Those bytes are stale\nconn-\u003edata contents and end up in the command\u0027s sense buffer, which is\nreturned to userspace.\n\nAccount for the 2-byte sense length prefix in the check."
        }
      ],
      "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 - A remote malicious or compromised iSCSI target can trigger the bug by sending a crafted SCSI Command Response over the standard iSCSI/TCP session to a Linux kernel initiator, with no local access required on the victim host.\nAC:L - The attacker fully controls the response PDU fields (datalen, sense length, CHECK_CONDITION status) and can reliably set datalen equal to senselen so the flawed bounds check passes and stale conn-\u003edata bytes are copied into the sense buffer.\nPR:N - Exploitation requires only the ability to act as the iSCSI target on the network; the attacker needs no local account, capabilities, or privileges on the victim system initiating the connection.\nUI:N - Once an iSCSI session exists, the leak is triggered automatically on SCSI command responses with no further victim action; the attacker does not rely on a user opening a file, clicking a link, or performing any interactive step at exploit time.\nS:U - The flaw discloses kernel memory contents into a SCSI sense buffer returned within the same host security domain; it does not cross VM, hypervisor, or IOMMU boundaries and is a standard kernel-to-userspace information leak.\nC:H - The out-of-bounds memcpy reads up to two bytes per response from stale conn-\u003edata kernel heap memory into sc-\u003esense_buffer, which is copied to userspace via SCSI completion, ioctl, and BSG paths, enabling repeated kernel information disclosure.\nI:N - The vulnerability is a read-only out-of-bounds memcpy from the receive buffer into the sense buffer; it does not corrupt kernel structures, overwrite memory, or provide a write or code-execution primitive.\nA:N - The bug causes no kernel panic, oops, or hang; invalid responses are handled gracefully and exploitation only leaks data into the sense buffer without disrupting system availability."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:48:39.750Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/7567f06abdefb1caf2d836107c4d08c5185c650e"
        },
        {
          "url": "https://git.kernel.org/stable/c/60499924faf4ef97e84228c20515218ef121facf"
        },
        {
          "url": "https://git.kernel.org/stable/c/3ef209ca0b4b68c75e9a814d90cc916026b5a6ac"
        },
        {
          "url": "https://git.kernel.org/stable/c/1f07a897d43c63e6c9458bf77450defef39b5833"
        },
        {
          "url": "https://git.kernel.org/stable/c/98b87885de4b7f605533a2860685f5689fce8e82"
        }
      ],
      "title": "scsi: libiscsi: Fix stale-data leak into the SCSI sense buffer",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74557",
    "datePublished": "2026-08-15T12:28:01.988Z",
    "dateReserved": "2026-08-15T05:44:03.916Z",
    "dateUpdated": "2026-08-17T05:48:39.750Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74557",
      "date": "2026-08-18",
      "epss": "0.00292",
      "percentile": "0.21747"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74557\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T13:18:01.160\",\"lastModified\":\"2026-08-17T06:19:53.803\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nscsi: libiscsi: Fix stale-data leak into the SCSI sense buffer\\n\\niscsi_scsi_cmd_rsp() copies the sense data of a SCSI Response from the\\ntarget-supplied data segment.  The segment carries a 2-byte sense length\\nfollowed by the sense bytes, so it must hold 2 + senselen bytes, but the\\nbounds check only requires datalen \u003e= senselen:\\n\\n\\tsenselen = get_unaligned_be16(data);\\n\\tif (datalen \u003c senselen)\\n\\t\\tgoto invalid_datalen;\\n\\tmemcpy(sc-\u003esense_buffer, data + 2,\\n\\t       min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));\\n\\nA target that returns a SCSI Response whose datalen equals senselen\\n(with senselen \u003c= SCSI_SENSE_BUFFERSIZE) makes the memcpy() from data +\\n2 read up to two bytes past the received data.  Those bytes are stale\\nconn-\u003edata contents and end up in the command\u0027s sense buffer, which is\\nreturned to userspace.\\n\\nAccount for the 2-byte sense length prefix in the check.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/scsi/libiscsi.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"7996a778ff8c717cb1a7a294475c59cc8f1e9fb8\",\"lessThan\":\"7567f06abdefb1caf2d836107c4d08c5185c650e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"7996a778ff8c717cb1a7a294475c59cc8f1e9fb8\",\"lessThan\":\"60499924faf4ef97e84228c20515218ef121facf\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"7996a778ff8c717cb1a7a294475c59cc8f1e9fb8\",\"lessThan\":\"3ef209ca0b4b68c75e9a814d90cc916026b5a6ac\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"7996a778ff8c717cb1a7a294475c59cc8f1e9fb8\",\"lessThan\":\"1f07a897d43c63e6c9458bf77450defef39b5833\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"7996a778ff8c717cb1a7a294475c59cc8f1e9fb8\",\"lessThan\":\"98b87885de4b7f605533a2860685f5689fce8e82\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/scsi/libiscsi.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"2.6.18\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"2.6.18\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.151\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.103\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.44\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.8\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"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/1f07a897d43c63e6c9458bf77450defef39b5833\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3ef209ca0b4b68c75e9a814d90cc916026b5a6ac\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/60499924faf4ef97e84228c20515218ef121facf\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/7567f06abdefb1caf2d836107c4d08c5185c650e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/98b87885de4b7f605533a2860685f5689fce8e82\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-08-17T16:25:11Z",
      "cve": "CVE-2026-74557",
      "id": "CVE-2026-74557",
      "initial_release_date": "2026-08-15T23:50:18Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-74557",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-74557.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.