FreeBSD ZFS up to p0.x/p6/p10/p15 Heal Receive Path ZFS_IOC_RECV_NEW memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.8$0-$5k0.00

Summaryinfo

A vulnerability was found in FreeBSD ZFS up to p0.x/p6/p10/p15. It has been classified as very critical. Affected by this vulnerability is the function ZFS_IOC_RECV_NEW of the component Heal Receive Path. This manipulation causes memory corruption. This vulnerability is tracked as CVE-2026-49430. The attack is restricted to local execution. No exploit exists.

Detailsinfo

A vulnerability classified as very critical was found in FreeBSD ZFS up to p0.x/p6/p10/p15. Affected by this vulnerability is the function ZFS_IOC_RECV_NEW of the component Heal Receive Path. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The ZFS_IOC_RECV_NEW ioctl, in the heal receive path, similarly truncated a 64-bit payload size to a 32-bit integer for allocation, then used the original 64-bit size as the length for a byteswap operation. A local user with the "receive" delegated ZFS permission can trigger kernel memory corruption via ZFS_IOC_RECV_NEW by sending a crafted receive stream in heal mode.

It is possible to read the advisory at security.freebsd.org. This vulnerability is known as CVE-2026-49430 since 05/29/2026. The exploitation appears to be easy. Attacking locally is a requirement. Additional levels of successful authentication are required for exploitation. 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 08/19/2026).

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

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 7.8

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
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: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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: 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-2026-49430 (🔒)
GCVE (CVE): GCVE-0-2026-49430
GCVE (VulDB): GCVE-100-392887

Entryinfo

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

Be aware that VulDB is the high quality source for vulnerability data.

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