Linux Kernel up to 7.1.3 partitions aix_partition pp_count out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k1.55-

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 7.1.3. This vulnerability affects the function aix_partition of the component partitions. The manipulation of the argument pp_count leads to out-of-bounds. This vulnerability is documented as CVE-2026-64318. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.1.3. It has been rated as problematic. This issue affects the function aix_partition of the component partitions. The manipulation of the argument pp_count with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: partitions: aix: bound the pp_count scan to the ppe array aix_partition() reads the physical volume descriptor into a fixed-size struct pvd and then scans its physical-partition-extent array: int numpps = be16_to_cpu(pvd->pp_count); ... for (i = 0; i < numpps; i += 1) { struct ppe *p = pvd->ppe + i; ... lp_ix = be16_to_cpu(p->lp_ix); pvd points at a single kmalloc()'d struct pvd whose ppe[] member holds a fixed ARRAY_SIZE(pvd->ppe) (1016) entries, but the loop runs up to the on-disk pp_count. pp_count is an unvalidated __be16 read straight from the descriptor, so a crafted AIX image with pp_count larger than 1016 drives the loop to read pvd->ppe[i] past the end of the allocation (up to 65535 entries, ~2 MB out of bounds). The partition scan runs without mounting anything, when a block device with a crafted AIX/IBM partition table appears (an attacker-supplied image attached with losetup -P, or a device auto-scanned by udev), via msdos_partition() -> aix_partition(). Clamp the scan to the number of entries the ppe[] array can hold.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-64318 since 07/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. The exploitation needs additional levels of successful authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/25/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4 or 7.2-rc1 eliminates this vulnerability. Applying the patch 09861651617ba0fec089e8b9477439e68398c110/5eacdb1967378f5e5591cd27a2d8cdee2df1a599/b5e9c09309e18fd9839ad007c238120353ca0cc4/fd94a779020f2ecc8b2607f4c20b34acb1763b9a/4671bb74bba05fdd4acf670a35758c29e8c97b83/ce93228e2193a17d2c58b656e439bb39fe5c3af8/44f37ee92fdcd377c41bdf6a31cdd8cc7d4c410e/2dc0bfd2fe355fb930de63c2f2eb8ced8570c579 is able to eliminate this problem.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.261/5.15.212/6.1.178/6.6.145/6.12.96/6.18.39/7.1.4/7.2-rc1
Patch: 09861651617ba0fec089e8b9477439e68398c110/5eacdb1967378f5e5591cd27a2d8cdee2df1a599/b5e9c09309e18fd9839ad007c238120353ca0cc4/fd94a779020f2ecc8b2607f4c20b34acb1763b9a/4671bb74bba05fdd4acf670a35758c29e8c97b83/ce93228e2193a17d2c58b656e439bb39fe5c3af8/44f37ee92fdcd377c41bdf6a31cdd8cc7d4c410e/2dc0bfd2fe355fb930de63c2f2eb8ced8570c579

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64318 (🔒)
GCVE (CVE): GCVE-0-2026-64318
GCVE (VulDB): GCVE-100-383111

Entryinfo

Created: 07/25/2026 15:13
Changes: 07/25/2026 15:13 (60)
Complete: 🔍
Cache ID: 216::103

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