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

CVE-2026-72213 (GCVE-0-2026-72213)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:54 – Updated: 2026-08-17 05:41
VLAI
Title
mm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch
Summary
In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch In alloc_hugetlb_folio(), a single h_cg pointer is used for both the rsvd and non-rsvd hugetlb cgroup charges. When map_chg is set, hugetlb_cgroup_charge_cgroup_rsvd() stores the charged cgroup in h_cg, but the immediately following hugetlb_cgroup_charge_cgroup() overwrites h_cg with the non-rsvd cgroup pointer. As a result, hugetlb_cgroup_commit_charge_rsvd() stores the wrong (non-rsvd) cgroup pointer into the folio's rsvd slot. When the folio is later freed, free_huge_folio() unconditionally calls both hugetlb_cgroup_uncharge_folio() and hugetlb_cgroup_uncharge_folio_rsvd(). The rsvd uncharge reads back the wrong cgroup from the folio and decrements a counter that was never charged for that cgroup, causing a page_counter underflow: page_counter underflow: -512 nr_pages=512 WARNING: mm/page_counter.c:61 at page_counter_cancel Fix this by introducing a separate h_cg_rsvd pointer exclusively for the rsvd charge path, keeping the rsvd and non-rsvd charges fully independent through their charge, commit, and error uncharge paths.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 08cf9faf7558020aed6a0da5810b824b07139dfa , < 5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd (git)
Affected: 08cf9faf7558020aed6a0da5810b824b07139dfa , < 1697d253f51cf5e3825a3423ff49e128a3502ab2 (git)
Affected: 08cf9faf7558020aed6a0da5810b824b07139dfa , < b785f2bd9496facedc0a031be09cddcd1d3c84d3 (git)
Affected: 08cf9faf7558020aed6a0da5810b824b07139dfa , < 15807d0ddde37407af72859426b654f3d1972b00 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 6.12.101 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 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": [
            "mm/hugetlb.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd",
              "status": "affected",
              "version": "08cf9faf7558020aed6a0da5810b824b07139dfa",
              "versionType": "git"
            },
            {
              "lessThan": "1697d253f51cf5e3825a3423ff49e128a3502ab2",
              "status": "affected",
              "version": "08cf9faf7558020aed6a0da5810b824b07139dfa",
              "versionType": "git"
            },
            {
              "lessThan": "b785f2bd9496facedc0a031be09cddcd1d3c84d3",
              "status": "affected",
              "version": "08cf9faf7558020aed6a0da5810b824b07139dfa",
              "versionType": "git"
            },
            {
              "lessThan": "15807d0ddde37407af72859426b654f3d1972b00",
              "status": "affected",
              "version": "08cf9faf7558020aed6a0da5810b824b07139dfa",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "mm/hugetlb.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.7"
            },
            {
              "lessThan": "5.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "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": "6.12.101",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch\n\nIn alloc_hugetlb_folio(), a single h_cg pointer is used for both the rsvd\nand non-rsvd hugetlb cgroup charges.  When map_chg is set,\nhugetlb_cgroup_charge_cgroup_rsvd() stores the charged cgroup in h_cg, but\nthe immediately following hugetlb_cgroup_charge_cgroup() overwrites h_cg\nwith the non-rsvd cgroup pointer.\n\nAs a result, hugetlb_cgroup_commit_charge_rsvd() stores the wrong\n(non-rsvd) cgroup pointer into the folio\u0027s rsvd slot.\n\nWhen the folio is later freed, free_huge_folio() unconditionally calls\nboth hugetlb_cgroup_uncharge_folio() and\nhugetlb_cgroup_uncharge_folio_rsvd().  The rsvd uncharge reads back the\nwrong cgroup from the folio and decrements a counter that was never\ncharged for that cgroup, causing a page_counter underflow:\n\n  page_counter underflow: -512 nr_pages=512\n  WARNING: mm/page_counter.c:61 at page_counter_cancel\n\nFix this by introducing a separate h_cg_rsvd pointer exclusively for the\nrsvd charge path, keeping the rsvd and non-rsvd charges fully independent\nthrough their charge, commit, and error uncharge paths."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is in alloc_hugetlb_folio()/free_huge_folio() and is reached only via local MM paths (mmap/munmap, hugetlb page faults, fallocate, memfd MFD_HUGETLB, MAP_HUGETLB) that syzbot triggered through hugetlbfs inode eviction, not via any network-facing kernel service.\nAC:L - An unprivileged attacker can reliably trigger the mismatch by creating hugetlbfs mappings without reservations (MAP_NORESERVE or fault-before-reserve), faulting in huge pages to run alloc_hugetlb_folio() with map_chg set, then closing/unmapping to free folios and hit the bad rsvd uncharge.\nPR:L - Triggering requires only an unprivileged local process that can use hugetlb memory (hugetlbfs/MAP_HUGETLB/memfd) under a hugetlb cgroup; no init-namespace root or special driver capabilities are needed, and cgroup hugetlb limits are controllable from user namespaces.\nUI:N - Exploitation is fully attacker-driven through normal syscalls (mmap, write/fault, close/unlink) and does not require any victim user action beyond the attacker operating on their own mappings.\nS:U - Impact is confined to kernel hugetlb/cgroup page_counter accounting within the same host kernel security domain; it does not cross VM, container runtime, or IOMMU boundaries.\nC:N - The flaw corrupts hugetlb cgroup reservation counters and emits a WARN on underflow; it does not read or disclose kernel memory, pointers, or other confidential data to the attacker.\nI:H - page_counter underflow forcibly resets hugetlb cgroup reservation usage to zero, corrupting kernel accounting so an attacker can bypass hugetlb.rsvd cgroup limits and consume hugepage resources beyond enforced quotas in multi-tenant/container deployments.\nA:H - free_huge_folio() unconditionally hits the bad rsvd uncharge and triggers a kernel WARNING/page_counter underflow during hugepage teardown; syzbot classified this as DoS and repeated alloc/free cycles can disrupt hugetlb availability for other workloads when limits are bypassed."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:41:39.361Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd"
        },
        {
          "url": "https://git.kernel.org/stable/c/1697d253f51cf5e3825a3423ff49e128a3502ab2"
        },
        {
          "url": "https://git.kernel.org/stable/c/b785f2bd9496facedc0a031be09cddcd1d3c84d3"
        },
        {
          "url": "https://git.kernel.org/stable/c/15807d0ddde37407af72859426b654f3d1972b00"
        }
      ],
      "title": "mm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72213",
    "datePublished": "2026-08-15T05:54:07.854Z",
    "dateReserved": "2026-08-09T03:40:39.912Z",
    "dateUpdated": "2026-08-17T05:41:39.361Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-72213",
      "date": "2026-09-04",
      "epss": "0.00159",
      "percentile": "0.05386"
    },
    "microsoft_vex": {
      "current_release_date": "2026-08-23T15:00:42.000Z",
      "cve": "CVE-2026-72213",
      "id": "msrc_CVE-2026-72213",
      "initial_release_date": "2026-08-23T15:00:42.000Z",
      "product_status:known_not_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "mm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-72213.json",
      "version": "1"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-72213\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T06:21:40.013\",\"lastModified\":\"2026-08-17T06:18:22.243\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nmm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch\\n\\nIn alloc_hugetlb_folio(), a single h_cg pointer is used for both the rsvd\\nand non-rsvd hugetlb cgroup charges.  When map_chg is set,\\nhugetlb_cgroup_charge_cgroup_rsvd() stores the charged cgroup in h_cg, but\\nthe immediately following hugetlb_cgroup_charge_cgroup() overwrites h_cg\\nwith the non-rsvd cgroup pointer.\\n\\nAs a result, hugetlb_cgroup_commit_charge_rsvd() stores the wrong\\n(non-rsvd) cgroup pointer into the folio\u0027s rsvd slot.\\n\\nWhen the folio is later freed, free_huge_folio() unconditionally calls\\nboth hugetlb_cgroup_uncharge_folio() and\\nhugetlb_cgroup_uncharge_folio_rsvd().  The rsvd uncharge reads back the\\nwrong cgroup from the folio and decrements a counter that was never\\ncharged for that cgroup, causing a page_counter underflow:\\n\\n  page_counter underflow: -512 nr_pages=512\\n  WARNING: mm/page_counter.c:61 at page_counter_cancel\\n\\nFix this by introducing a separate h_cg_rsvd pointer exclusively for the\\nrsvd charge path, keeping the rsvd and non-rsvd charges fully independent\\nthrough their charge, commit, and error uncharge paths.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"mm/hugetlb.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"08cf9faf7558020aed6a0da5810b824b07139dfa\",\"lessThan\":\"5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"08cf9faf7558020aed6a0da5810b824b07139dfa\",\"lessThan\":\"1697d253f51cf5e3825a3423ff49e128a3502ab2\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"08cf9faf7558020aed6a0da5810b824b07139dfa\",\"lessThan\":\"b785f2bd9496facedc0a031be09cddcd1d3c84d3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"08cf9faf7558020aed6a0da5810b824b07139dfa\",\"lessThan\":\"15807d0ddde37407af72859426b654f3d1972b00\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"mm/hugetlb.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.7\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.7\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.101\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.40\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.5\",\"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/15807d0ddde37407af72859426b654f3d1972b00\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/1697d253f51cf5e3825a3423ff49e128a3502ab2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b785f2bd9496facedc0a031be09cddcd1d3c84d3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-18T16:29:13+00:00",
      "cve": "CVE-2026-72213",
      "id": "CVE-2026-72213",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "246",
      "product_status:known_not_affected": "28",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: mm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-72213.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.