---
cve: "CVE-2026-64318"
severity: "HIGH"
cvss: 7.1
epss: "16%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-07-25 10:17:13"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-12T07:04:02+02:00"
---

# CVE-2026-64318

> 7.1 HIGH

## Beschreibung

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.

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Keine | good |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- Kernel ≥ 5.10.261
- Kernel ≥ 5.15.212
- Kernel ≥ 6.1.178
- Kernel ≥ 6.6.145
- Kernel ≥ 6.12.96
- Kernel ≥ 6.18.39
- Kernel ≥ 7.1.4

## Referenzen

- <https://git.kernel.org/stable/c/09861651617ba0fec089e8b9477439e68398c110>
- <https://git.kernel.org/stable/c/5eacdb1967378f5e5591cd27a2d8cdee2df1a599>
- <https://git.kernel.org/stable/c/b5e9c09309e18fd9839ad007c238120353ca0cc4>
- <https://git.kernel.org/stable/c/fd94a779020f2ecc8b2607f4c20b34acb1763b9a>
- <https://git.kernel.org/stable/c/4671bb74bba05fdd4acf670a35758c29e8c97b83>
- <https://git.kernel.org/stable/c/ce93228e2193a17d2c58b656e439bb39fe5c3af8>
- <https://git.kernel.org/stable/c/44f37ee92fdcd377c41bdf6a31cdd8cc7d4c410e>
- <https://git.kernel.org/stable/c/2dc0bfd2fe355fb930de63c2f2eb8ced8570c579>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-64318) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_