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CVE-2026-64501

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: iio: adc: ad_sigma_delta: fix CS held asserted and state leaks In ad_sigma_delta_single_conversion(), set_mode(AD_SD_MODE_IDLE) and disable_one() were called from the out: block while keep_cs_asserted was still true. This caused any SPI transfer issued by those callbacks to carry cs_change=1, leaving CS permanently asserted after the conversion. Fix by moving both calls into the out_unlock: block, after keep_cs_asserted is cleared, matching the pattern already used in ad_sd_calibrate(). In the error path of ad_sd_buffer_postenable(), if an operation fails after set_mode(AD_SD_MODE_CONTINUOUS) has already succeeded (e.g. spi_offload_trigger_enable()), the device is left in continuous conversion mode with CS physically asserted. Additionally, bus_locked remaining true after spi_bus_unlock() causes subsequent SPI operations to call spi_sync_locked() without the bus lock actually held, allowing concurrent SPI access. Fix the error path by clearing keep_cs_asserted first, then calling set_mode(AD_SD_MODE_IDLE) to revert the device mode and deassert CS, then clearing bus_locked before releasing the bus. For devices that implement neither set_mode nor disable_one (such as MAX11205, which has no physical CS pin), no SPI transfer is issued during cleanup and the cs_change flag has no effect on any physical line.

Severity
HIGH
CVSS score
7.1 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:36.090000
Last modified
2026-11-03 18:15:39.353000
View original CVE JSON
{
  "id": "CVE-2026-64501",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-25T10:17:36.090",
  "lastModified": "2026-11-03T18:15:39.353",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niio: adc: ad_sigma_delta: fix CS held asserted and state leaks\n\nIn ad_sigma_delta_single_conversion(), set_mode(AD_SD_MODE_IDLE) and\ndisable_one() were called from the out: block while keep_cs_asserted\nwas still true. This caused any SPI transfer issued by those callbacks\nto carry cs_change=1, leaving CS permanently asserted after the\nconversion. Fix by moving both calls into the out_unlock: block, after\nkeep_cs_asserted is cleared, matching the pattern already used in\nad_sd_calibrate().\n\nIn the error path of ad_sd_buffer_postenable(), if an operation fails\nafter set_mode(AD_SD_MODE_CONTINUOUS) has already succeeded (e.g.\nspi_offload_trigger_enable()), the device is left in continuous\nconversion mode with CS physically asserted. Additionally,\nbus_locked remaining true after spi_bus_unlock() causes subsequent\nSPI operations to call spi_sync_locked() without the bus lock actually\nheld, allowing concurrent SPI access.\n\nFix the error path by clearing keep_cs_asserted first, then calling\nset_mode(AD_SD_MODE_IDLE) to revert the device mode and deassert CS,\nthen clearing bus_locked before releasing the bus.\n\nFor devices that implement neither set_mode nor disable_one (such as\nMAX11205, which has no physical CS pin), no SPI transfer is issued\nduring cleanup and the cs_change flag has no effect on any physical\nline."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/iio/adc/ad_sigma_delta.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "132d44dc6966c1cf841ffe0f6f048165687e870b",
              "lessThan": "c313bb7c38855e94ceef939d152dd75e5a904b5f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "132d44dc6966c1cf841ffe0f6f048165687e870b",
              "lessThan": "f1de829ee87a1198d3465493ce430d36c5fa029c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "132d44dc6966c1cf841ffe0f6f048165687e870b",
              "lessThan": "c72da0688575e5ef39c36bb44fed53aa18f8ae65",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/iio/adc/ad_sigma_delta.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.14",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.14",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.39",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.4",
              "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:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.2
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/c313bb7c38855e94ceef939d152dd75e5a904b5f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c72da0688575e5ef39c36bb44fed53aa18f8ae65",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f1de829ee87a1198d3465493ce430d36c5fa029c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}