CVE-2026-64323 (GCVE-0-2026-64323)
Vulnerability from cvelistv5 – Published: 2026-07-25 08:49 – Updated: 2026-07-27 04:59
VLAI
EPSS
VEX
Title
udf: validate VAT header length against the VAT inode size
Summary
In the Linux kernel, the following vulnerability has been resolved:
udf: validate VAT header length against the VAT inode size
udf_load_vat() takes the virtual partition's start offset straight from
the on-disk VAT 2.0 header without checking it against the VAT inode
size:
map->s_type_specific.s_virtual.s_start_offset =
le16_to_cpu(vat20->lengthHeader);
map->s_type_specific.s_virtual.s_num_entries =
(sbi->s_vat_inode->i_size -
map->s_type_specific.s_virtual.s_start_offset) >> 2;
lengthHeader is a fully attacker-controlled 16-bit value. If it exceeds
the VAT inode size, the s_num_entries subtraction underflows to a huge
count, which defeats the "block > s_num_entries" bound in
udf_get_pblock_virt15(); and on the ICB-inline path that function reads
((__le32 *)(iinfo->i_data + s_start_offset))[block]
so a large s_start_offset indexes past the inode's in-ICB data. Mounting
a crafted UDF image with a virtual (VAT) partition then triggers an
out-of-bounds read.
Reject a VAT whose header length does not leave room for at least one
entry within the VAT inode.
Severity
7.1 (High)
Assigner
References
8 references
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| Linux | Linux |
Affected:
fa5e08156335d0687c85b4e724db9448fb166601 , < 0ad2d09a8d66fa8dc6f9b70d660b5fb4478ea934
(git)
Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < 883962731420ec271ed8c1cd76524f4b17faa982 (git) Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < 2900e02a0dd4fc30ac9840e7ce4ca0b041ab0d63 (git) Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < bb0d384c1f42a5b7ace0bd88fee80b9bb1d49acb (git) Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < 55287a3555ff0515b3aff181d2c08c0462a41709 (git) Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < e610fb113cdfa8bf4247c9bf4f2337b81ad4ddad (git) Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < 74580fdf022909e184223cacc364feb826982d96 (git) Affected: fa5e08156335d0687c85b4e724db9448fb166601 , < d8202786b3d75125c84ebc4de6d946f92fde0ee8 (git) |
|
| Linux | Linux |
Affected:
2.6.26
Unaffected: 0 , < 2.6.26 (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-rc1 , ≤ * (original_commit_for_fix) |
{
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nudf: validate VAT header length against the VAT inode size\n\nudf_load_vat() takes the virtual partition\u0027s start offset straight from\nthe on-disk VAT 2.0 header without checking it against the VAT inode\nsize:\n\n\tmap-\u003es_type_specific.s_virtual.s_start_offset =\n\t\tle16_to_cpu(vat20-\u003elengthHeader);\n\tmap-\u003es_type_specific.s_virtual.s_num_entries =\n\t\t(sbi-\u003es_vat_inode-\u003ei_size -\n\t\t\tmap-\u003es_type_specific.s_virtual.s_start_offset) \u003e\u003e 2;\n\nlengthHeader is a fully attacker-controlled 16-bit value. If it exceeds\nthe VAT inode size, the s_num_entries subtraction underflows to a huge\ncount, which defeats the \"block \u003e s_num_entries\" bound in\nudf_get_pblock_virt15(); and on the ICB-inline path that function reads\n\n\t((__le32 *)(iinfo-\u003ei_data + s_start_offset))[block]\n\nso a large s_start_offset indexes past the inode\u0027s in-ICB data. Mounting\na crafted UDF image with a virtual (VAT) partition then triggers an\nout-of-bounds read.\n\nReject a VAT whose header length does not leave room for at least one\nentry within the VAT inode."
}
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"datePublished": "2026-07-25T08:49:51.097Z",
"dateReserved": "2026-07-19T15:36:31.780Z",
"dateUpdated": "2026-07-27T04:59:49.230Z",
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If it exceeds\\nthe VAT inode size, the s_num_entries subtraction underflows to a huge\\ncount, which defeats the \\\"block \u003e s_num_entries\\\" bound in\\nudf_get_pblock_virt15(); and on the ICB-inline path that function reads\\n\\n\\t((__le32 *)(iinfo-\u003ei_data + s_start_offset))[block]\\n\\nso a large s_start_offset indexes past the inode\u0027s in-ICB data. Mounting\\na crafted UDF image with a virtual (VAT) partition then triggers an\\nout-of-bounds read.\\n\\nReject a VAT whose header length does not leave room for at least one\\nentry within the VAT inode.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/udf/super.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"0ad2d09a8d66fa8dc6f9b70d660b5fb4478ea934\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"883962731420ec271ed8c1cd76524f4b17faa982\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"2900e02a0dd4fc30ac9840e7ce4ca0b041ab0d63\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"bb0d384c1f42a5b7ace0bd88fee80b9bb1d49acb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"55287a3555ff0515b3aff181d2c08c0462a41709\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"e610fb113cdfa8bf4247c9bf4f2337b81ad4ddad\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"74580fdf022909e184223cacc364feb826982d96\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fa5e08156335d0687c85b4e724db9448fb166601\",\"lessThan\":\"d8202786b3d75125c84ebc4de6d946f92fde0ee8\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/udf/super.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"2.6.26\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"2.6.26\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.261\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.212\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.96\",\"lessThanOrEqual\":\"6.12.*\",\"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-rc1\",\"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:H/I:N/A:H\",\"baseScore\":7.1,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.2}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0ad2d09a8d66fa8dc6f9b70d660b5fb4478ea934\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/2900e02a0dd4fc30ac9840e7ce4ca0b041ab0d63\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/55287a3555ff0515b3aff181d2c08c0462a41709\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/74580fdf022909e184223cacc364feb826982d96\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/883962731420ec271ed8c1cd76524f4b17faa982\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/bb0d384c1f42a5b7ace0bd88fee80b9bb1d49acb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d8202786b3d75125c84ebc4de6d946f92fde0ee8\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/e610fb113cdfa8bf4247c9bf4f2337b81ad4ddad\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
"suse_vex": {
"aggregate_severity": "not set",
"current_release_date": "2026-07-25T16:45:43Z",
"cve": "CVE-2026-64323",
"id": "CVE-2026-64323",
"initial_release_date": "2026-07-25T16:45:43Z",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-64323",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64323.json",
"version": "2"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
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