CVE-2026-64504 (GCVE-0-2026-64504)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:51 – Updated: 2026-08-17 04:56
VLAI
Title
iio: accel: bmc150: clamp the device-reported FIFO frame count
Summary
In the Linux kernel, the following vulnerability has been resolved: iio: accel: bmc150: clamp the device-reported FIFO frame count __bmc150_accel_fifo_flush() copies the number of samples the device reports in its hardware FIFO into an on-stack buffer u16 buffer[BMC150_ACCEL_FIFO_LENGTH * 3]; which is sized for at most BMC150_ACCEL_FIFO_LENGTH (32) samples. The frame count is read from the FIFO_STATUS register and only masked to its 7 valid bits: count = val & 0x7F; so it can be 0..127. The only other limit applied to it is the optional caller-supplied sample budget: if (samples && count > samples) count = samples; which does not constrain count on the flush-all path (samples == 0), and leaves it well above 32 whenever samples is larger. count samples are then transferred into buffer[]: bmc150_accel_fifo_transfer(data, (u8 *)buffer, count); bmc150_accel_fifo_transfer() reads count * 6 bytes through regmap, so a malfunctioning, malicious or counterfeit accelerometer (or an attacker tampering with the I2C/SPI bus) that reports up to 127 frames writes up to 762 bytes into the 192-byte buffer: a stack out-of-bounds write of up to 570 bytes that clobbers the stack canary, saved registers and the return address. Clamp count to BMC150_ACCEL_FIFO_LENGTH, the number of samples buffer[] is sized for, before the transfer, mirroring the watermark clamp already done in bmc150_accel_set_watermark(). A well-formed flush reports at most BMC150_ACCEL_FIFO_LENGTH frames, so legitimate devices are unaffected.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < b5a9f521e0a49a0266200fd535b32a9668ecb33b (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < 2fe0531dd73eff1de0f2584cb77716d645e548d5 (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < d0e6d924a5484e005cae5aff6a0aa07a22f3c9ff (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < bfffc98f3de92e0f76be7c7b72e63ac1776a6dbc (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < 89f4a4ca0ac3a933c750569a771c079a290b0721 (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < 3e766526827acd542bcd36c20c4d5f397e0f6521 (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < 35a3cd8fd65e15029eb90f1e510045b1bb071175 (git)
Affected: 3bbec9773389112330954a6a64422eaa78d546c1 , < ce0e1cae26096fe959a0da5563a6d6d5a801d5fb (git)
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Linux Linux Affected: 4.1
Unaffected: 0 , < 4.1 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.96 , ≤ 6.12.* (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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{
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          "url": "https://git.kernel.org/stable/c/ce0e1cae26096fe959a0da5563a6d6d5a801d5fb"
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    "dateReserved": "2026-07-19T15:36:31.793Z",
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niio: accel: bmc150: clamp the device-reported FIFO frame count\n\n__bmc150_accel_fifo_flush() copies the number of samples the device\nreports in its hardware FIFO into an on-stack buffer\n\n\tu16 buffer[BMC150_ACCEL_FIFO_LENGTH * 3];\n\nwhich is sized for at most BMC150_ACCEL_FIFO_LENGTH (32) samples. The\nframe count is read from the FIFO_STATUS register and only masked to its\n7 valid bits:\n\n\tcount = val \u0026 0x7F;\n\nso it can be 0..127. The only other limit applied to it is the optional\ncaller-supplied sample budget:\n\n\tif (samples \u0026\u0026 count \u003e samples)\n\t\tcount = samples;\n\nwhich does not constrain count on the flush-all path (samples == 0), and\nleaves it well above 32 whenever samples is larger. count samples are\nthen transferred into buffer[]:\n\n\tbmc150_accel_fifo_transfer(data, (u8 *)buffer, count);\n\nbmc150_accel_fifo_transfer() reads count * 6 bytes through regmap, so a\nmalfunctioning, malicious or counterfeit accelerometer (or an attacker\ntampering with the I2C/SPI bus) that reports up to 127 frames writes up\nto 762 bytes into the 192-byte buffer: a stack out-of-bounds write of up\nto 570 bytes that clobbers the stack canary, saved registers and the\nreturn address.\n\nClamp count to BMC150_ACCEL_FIFO_LENGTH, the number of samples buffer[]\nis sized for, before the transfer, mirroring the watermark clamp already\ndone in bmc150_accel_set_watermark(). A well-formed flush reports at most\nBMC150_ACCEL_FIFO_LENGTH frames, so legitimate devices are unaffected."
          }
        ],
        "id": "CVE-2026-64504",
        "lastModified": "2026-08-17T05:17:56.503",
        "metrics": {},
        "published": "2026-07-25T10:17:36.443",
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            "url": "https://git.kernel.org/stable/c/d0e6d924a5484e005cae5aff6a0aa07a22f3c9ff"
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        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
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    },
    "redhat_vex": {
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      "current_release_date": "2026-07-30T05:41:18+00:00",
      "cve": "CVE-2026-64504",
      "id": "CVE-2026-64504",
      "initial_release_date": "2026-07-25T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: iio: accel: bmc150: clamp the device-reported FIFO frame count",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64504.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-18T00:39:08Z",
      "cve": "CVE-2026-64504",
      "id": "CVE-2026-64504",
      "initial_release_date": "2026-07-25T15:58:07Z",
      "product_status:known_affected": "671",
      "product_status:known_not_affected": "62",
      "product_status:recommended": "111",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64504",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64504.json",
      "version": "12"
    }
  }
}



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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.



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.