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

CVE-2026-46130 (GCVE-0-2026-46130)

Vulnerability from cvelistv5 – Published: 2026-05-28 09:35 – Updated: 2026-08-03 09:32
VLAI
Title
dm-verity-fec: fix reading parity bytes split across blocks (take 3)
Summary
In the Linux kernel, the following vulnerability has been resolved: dm-verity-fec: fix reading parity bytes split across blocks (take 3) fec_decode_bufs() assumes that the parity bytes of the first RS codeword it decodes are never split across parity blocks. This assumption is false. Consider v->fec->block_size == 4096 && v->fec->roots == 17 && fio->nbufs == 1, for example. In that case, each call to fec_decode_bufs() consumes v->fec->roots * (fio->nbufs << DM_VERITY_FEC_BUF_RS_BITS) = 272 parity bytes. Considering that the parity data for each message block starts on a block boundary, the byte alignment in the parity data will iterate through 272*i mod 4096 until the 3 parity blocks have been consumed. On the 16th call (i=15), the alignment will be 4080 bytes into the first block. Only 16 bytes remain in that block, but 17 parity bytes will be needed. The code reads out-of-bounds from the parity block buffer. Fortunately this doesn't normally happen, since it can occur only for certain non-default values of fec_roots *and* when the maximum number of buffers couldn't be allocated due to low memory. For example with block_size=4096 only the following cases are affected: fec_roots=17: nbufs in [1, 3, 5, 15] fec_roots=19: nbufs in [1, 229] fec_roots=21: nbufs in [1, 3, 5, 13, 15, 39, 65, 195] fec_roots=23: nbufs in [1, 89] Regardless, fix it by refactoring how the parity blocks are read.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 6df90c02bae468a3a6110bafbc659884d0c4966c , < d47281b9a4472cfd73122393e79fbe76b651e46a (git)
Affected: 6df90c02bae468a3a6110bafbc659884d0c4966c , < 3d1b4e2d8ac0a1a1390a117f61ce0ca1c47e3bcb (git)
Affected: 6df90c02bae468a3a6110bafbc659884d0c4966c , < 430a05cb926f6bdf53e81460a2c3a553257f3f61 (git)
Affected: 6bc6ee31113b05db605694491bdeb2b1730142f1 (git)
Affected: 12caa73a28f0ae147ec0356b45091edf2462462b (git)
Affected: fc8943886629e26de34867db302c74d465510826 (git)
Affected: 6.1.125 , < 6.2 (semver)
Affected: 6.6.72 , < 6.7 (semver)
Affected: 6.12.10 , < 6.13 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 6.13
Unaffected: 0 , < 6.13 (semver)
Unaffected: 6.18.42 , ≤ 6.18.* (semver)
Unaffected: 7.0.7 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (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/md/dm-verity-fec.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d47281b9a4472cfd73122393e79fbe76b651e46a",
              "status": "affected",
              "version": "6df90c02bae468a3a6110bafbc659884d0c4966c",
              "versionType": "git"
            },
            {
              "lessThan": "3d1b4e2d8ac0a1a1390a117f61ce0ca1c47e3bcb",
              "status": "affected",
              "version": "6df90c02bae468a3a6110bafbc659884d0c4966c",
              "versionType": "git"
            },
            {
              "lessThan": "430a05cb926f6bdf53e81460a2c3a553257f3f61",
              "status": "affected",
              "version": "6df90c02bae468a3a6110bafbc659884d0c4966c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "6bc6ee31113b05db605694491bdeb2b1730142f1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "12caa73a28f0ae147ec0356b45091edf2462462b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fc8943886629e26de34867db302c74d465510826",
              "versionType": "git"
            },
            {
              "lessThan": "6.2",
              "status": "affected",
              "version": "6.1.125",
              "versionType": "semver"
            },
            {
              "lessThan": "6.7",
              "status": "affected",
              "version": "6.6.72",
              "versionType": "semver"
            },
            {
              "lessThan": "6.13",
              "status": "affected",
              "version": "6.12.10",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/md/dm-verity-fec.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.13"
            },
            {
              "lessThan": "6.13",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.42",
                  "versionStartIncluding": "6.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.7",
                  "versionStartIncluding": "6.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1",
                  "versionStartIncluding": "6.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.1.125",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.6.72",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.12.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm-verity-fec: fix reading parity bytes split across blocks (take 3)\n\nfec_decode_bufs() assumes that the parity bytes of the first RS codeword\nit decodes are never split across parity blocks.\n\nThis assumption is false.  Consider v-\u003efec-\u003eblock_size == 4096 \u0026\u0026\nv-\u003efec-\u003eroots == 17 \u0026\u0026 fio-\u003enbufs == 1, for example.  In that case, each\ncall to fec_decode_bufs() consumes v-\u003efec-\u003eroots * (fio-\u003enbufs \u003c\u003c\nDM_VERITY_FEC_BUF_RS_BITS) = 272 parity bytes.\n\nConsidering that the parity data for each message block starts on a\nblock boundary, the byte alignment in the parity data will iterate\nthrough 272*i mod 4096 until the 3 parity blocks have been consumed.  On\nthe 16th call (i=15), the alignment will be 4080 bytes into the first\nblock.  Only 16 bytes remain in that block, but 17 parity bytes will be\nneeded.  The code reads out-of-bounds from the parity block buffer.\n\nFortunately this doesn\u0027t normally happen, since it can occur only for\ncertain non-default values of fec_roots *and* when the maximum number of\nbuffers couldn\u0027t be allocated due to low memory.  For example with\nblock_size=4096 only the following cases are affected:\n\n    fec_roots=17: nbufs in [1, 3, 5, 15]\n    fec_roots=19: nbufs in [1, 229]\n    fec_roots=21: nbufs in [1, 3, 5, 13, 15, 39, 65, 195]\n    fec_roots=23: nbufs in [1, 89]\n\nRegardless, fix it by refactoring how the parity blocks are read."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-03T09:32:32.606Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/d47281b9a4472cfd73122393e79fbe76b651e46a"
        },
        {
          "url": "https://git.kernel.org/stable/c/3d1b4e2d8ac0a1a1390a117f61ce0ca1c47e3bcb"
        },
        {
          "url": "https://git.kernel.org/stable/c/430a05cb926f6bdf53e81460a2c3a553257f3f61"
        }
      ],
      "title": "dm-verity-fec: fix reading parity bytes split across blocks (take 3)",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-46130",
    "datePublished": "2026-05-28T09:35:45.387Z",
    "dateReserved": "2026-05-13T15:03:33.099Z",
    "dateUpdated": "2026-08-03T09:32:32.606Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-46130",
      "date": "2026-09-19",
      "epss": "0.00124",
      "percentile": "0.02461"
    },
    "microsoft_vex": {
      "current_release_date": "2026-06-28T01:50:53.000Z",
      "cve": "CVE-2026-46130",
      "id": "msrc_CVE-2026-46130",
      "initial_release_date": "2026-05-02T00:00:00.000Z",
      "product_status:known_affected": "3",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "dm-verity-fec: fix reading parity bytes split across blocks (take 3)",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-46130.json",
      "version": "4"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "drivers/md/dm-verity-fec.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "d47281b9a4472cfd73122393e79fbe76b651e46a",
                    "status": "affected",
                    "version": "6df90c02bae468a3a6110bafbc659884d0c4966c",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "3d1b4e2d8ac0a1a1390a117f61ce0ca1c47e3bcb",
                    "status": "affected",
                    "version": "6df90c02bae468a3a6110bafbc659884d0c4966c",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "430a05cb926f6bdf53e81460a2c3a553257f3f61",
                    "status": "affected",
                    "version": "6df90c02bae468a3a6110bafbc659884d0c4966c",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "6bc6ee31113b05db605694491bdeb2b1730142f1",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "12caa73a28f0ae147ec0356b45091edf2462462b",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "fc8943886629e26de34867db302c74d465510826",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "6.2",
                    "status": "affected",
                    "version": "6.1.125",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.7",
                    "status": "affected",
                    "version": "6.6.72",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "6.13",
                    "status": "affected",
                    "version": "6.12.10",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "drivers/md/dm-verity-fec.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.13"
                  },
                  {
                    "lessThan": "6.13",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.42",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.0.*",
                    "status": "unaffected",
                    "version": "7.0.7",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.1",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "11083F03-2811-4C72-9E18-287C2EE4B3BE",
                    "versionEndExcluding": "6.2",
                    "versionStartIncluding": "6.1.125",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "0307D505-E29B-475B-99D8-D3978D39E7DD",
                    "versionEndExcluding": "6.7",
                    "versionStartIncluding": "6.6.72",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "1EFFAF09-76E6-408C-A76D-D9ACB7B92EAA",
                    "versionEndExcluding": "6.13",
                    "versionStartIncluding": "6.12.10",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "3305D327-0CC2-4C16-9291-5F57A56171E7",
                    "versionEndExcluding": "7.0.7",
                    "versionStartIncluding": "6.13.1",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:*",
                    "matchCriteriaId": "5A3F9505-6B98-4269-8B81-127E55A1BF00",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:*",
                    "matchCriteriaId": "5DFCDFB8-4FD0-465A-9076-D813D78FE51B",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm-verity-fec: fix reading parity bytes split across blocks (take 3)\n\nfec_decode_bufs() assumes that the parity bytes of the first RS codeword\nit decodes are never split across parity blocks.\n\nThis assumption is false.  Consider v-\u003efec-\u003eblock_size == 4096 \u0026\u0026\nv-\u003efec-\u003eroots == 17 \u0026\u0026 fio-\u003enbufs == 1, for example.  In that case, each\ncall to fec_decode_bufs() consumes v-\u003efec-\u003eroots * (fio-\u003enbufs \u003c\u003c\nDM_VERITY_FEC_BUF_RS_BITS) = 272 parity bytes.\n\nConsidering that the parity data for each message block starts on a\nblock boundary, the byte alignment in the parity data will iterate\nthrough 272*i mod 4096 until the 3 parity blocks have been consumed.  On\nthe 16th call (i=15), the alignment will be 4080 bytes into the first\nblock.  Only 16 bytes remain in that block, but 17 parity bytes will be\nneeded.  The code reads out-of-bounds from the parity block buffer.\n\nFortunately this doesn\u0027t normally happen, since it can occur only for\ncertain non-default values of fec_roots *and* when the maximum number of\nbuffers couldn\u0027t be allocated due to low memory.  For example with\nblock_size=4096 only the following cases are affected:\n\n    fec_roots=17: nbufs in [1, 3, 5, 15]\n    fec_roots=19: nbufs in [1, 229]\n    fec_roots=21: nbufs in [1, 3, 5, 13, 15, 39, 65, 195]\n    fec_roots=23: nbufs in [1, 89]\n\nRegardless, fix it by refactoring how the parity blocks are read."
          }
        ],
        "id": "CVE-2026-46130",
        "lastModified": "2026-08-03T10:16:29.100",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.1,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.2,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2026-05-28T10:16:28.570",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/3d1b4e2d8ac0a1a1390a117f61ce0ca1c47e3bcb"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/430a05cb926f6bdf53e81460a2c3a553257f3f61"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/d47281b9a4472cfd73122393e79fbe76b651e46a"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Undergoing Analysis",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-125"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-06-27T16:20:51+00:00",
      "cve": "CVE-2026-46130",
      "id": "CVE-2026-46130",
      "initial_release_date": "2026-05-28T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: dm-verity-fec: fix reading parity bytes split across blocks (take 3)",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46130.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T01:12:08Z",
      "cve": "CVE-2026-46130",
      "id": "CVE-2026-46130",
      "initial_release_date": "2026-05-29T01:16:39Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "91",
      "product_status:known_not_affected": "279",
      "product_status:recommended": "149",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-46130",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-46130.json",
      "version": "9"
    }
  }
}



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.