VDB-392888 · CVE-2026-49431 · GCVE-0-2026-49431

FreeBSD ZFS up to p0.x/p6/p10/p15 ZFS_IOC_SET_PROP hasrecvd improper authorization

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4.2	$0-$5k	0.00

Summaryinfo

A vulnerability was found in FreeBSD ZFS up to p0.x/p6/p10/p15. It has been declared as problematic. Affected by this issue is the function ZFS_IOC_SET_PROP. Such manipulation of the argument hasrecvd leads to improper authorization. This vulnerability is listed as CVE-2026-49431. The attack must be carried out locally. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in FreeBSD ZFS up to p0.x/p6/p10/p15. Affected by this issue is the function ZFS_IOC_SET_PROP. The manipulation of the argument hasrecvd with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is integrity, and availability. CVE summarizes:

The ZFS_IOC_SET_PROP ioctl, used by zfs-set(8), incorrectly validated the calling user such that an unprivileged user is able to set metadata on a dataset indicating that the dataset has received properties from a zfs-recv(8) stream. Any local user can set the internal ZFS metadata flag "$hasrecvd" on datasets via ZFS_IOC_SET_PROP.

The advisory is shared for download at security.freebsd.org. This vulnerability is handled as CVE-2026-49431 since 05/29/2026. The exploitation is known to be easy. The attack needs to be approached locally. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version p1, p7, p11 or p16 eliminates this vulnerability.

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Productinfo

Type

Operating System

Vendor

FreeBSD

Name

Version

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.4
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: ZFS p1/p7/p11/p16

Timelineinfo

05/29/2026 CVE reserved
08/19/2026 +82 days Advisory disclosed
08/19/2026 +0 days VulDB entry created
08/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: security.freebsd.org
Status: Confirmed

CVE: CVE-2026-49431 (🔒)
GCVE (CVE): GCVE-0-2026-49431
GCVE (VulDB): GCVE-100-392888

Entryinfo

Created: 08/19/2026 07:30
Changes: 08/19/2026 07:30 (56)
Complete: 🔍
Cache ID: 216::103