CVE-2026-63995 (GCVE-0-2026-63995)

Vulnerability from cvelistv5 – Published: 2026-07-19 14:56 – Updated: 2026-07-20 13:42
VLAI
Title
ethtool: cmis: validate start_cmd_payload_size from module
Summary
In the Linux kernel, the following vulnerability has been resolved: ethtool: cmis: validate start_cmd_payload_size from module The CMIS firmware update code reads start_cmd_payload_size from the module's FW Management Features CDB reply and uses it directly as the byte count for memcpy. The destination buffer is 112 bytes (ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH - 8). So a malicious module (or corrupted response) can cause a OOB write later on in cmis_fw_update_start_download(). Let's error out. If modules that expect longer LPL writes actually exist we should revisit. struct cmis_cdb_start_fw_download_pl's definition has to move, no change there.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: c4f78134d45c9619339c96b4bea380b1d0699788 , < 63112b4515469d00008452d9cfe3fb3bf1aa2df3 (git)
Affected: c4f78134d45c9619339c96b4bea380b1d0699788 , < 0696709e951be54c699664adf546d16e28974d53 (git)
Affected: c4f78134d45c9619339c96b4bea380b1d0699788 , < a46340da00385be7fb16c62425ebc20006f2d5d8 (git)
Affected: c4f78134d45c9619339c96b4bea380b1d0699788 , < 12c2496a71f82f63617971ca9b730dffa05cf58b (git)
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Linux Linux Affected: 6.11
Unaffected: 0 , < 6.11 (semver)
Unaffected: 6.12.93 , ≤ 6.12.* (semver)
Unaffected: 6.18.35 , ≤ 6.18.* (semver)
Unaffected: 7.0.12 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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          "programFiles": [
            "net/ethtool/cmis_fw_update.c"
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        }
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    "datePublished": "2026-07-19T14:56:14.580Z",
    "dateReserved": "2026-07-19T07:54:57.026Z",
    "dateUpdated": "2026-07-20T13:42:10.891Z",
    "state": "PUBLISHED"
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  }
}



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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

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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.