CVE-2026-49429

HIGH
MEDIUM Priority: 0.01 BB Relevance: 41/100
Published: 2026-08-19 Modified: 2026-11-09 First seen: 2026-11-09 Status: active

Attack Surface

Low Complexity No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: High
I: High
A: High

Description

The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records. A local user with the "userused" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.

Weakness Classification (1)

Affected Software (38)

Showing 30 of 38 entries

References & Advisories (1)

Bug Bounty Relevance

41 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.8 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.15%
Raw Score 0.001530
Percentile 4.5%
Date 2026-11-14

EPSS Trend

2026-11-14
0.00153
2026-11-13
0.00153
2026-11-12
0.00153
2026-11-10
0.00153
2026-11-09
0.00153

Intelligence Sources

nvd ref →