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… (CVE-2026-49430)
A vulnerability exists in the ZFS_IOC_RECV_NEW ioctl in the heal receive path where a 64-bit payload size is truncated to a 32-bit integer for allocation but the original 64-bit size is used for a byteswap operation. This flaw allows a local user with delegated ZFS receive permission to cause kernel memory corruption by sending a specially crafted receive stream in heal mode.
AI Analysis
Technical Summary
The ZFS_IOC_RECV_NEW ioctl in the ZFS filesystem's heal receive path improperly truncates a 64-bit payload size to a 32-bit integer when allocating memory, but subsequently uses the original 64-bit size for a byteswap operation. This mismatch can lead to kernel memory corruption. Exploitation requires local access with the delegated 'receive' ZFS permission and involves sending a crafted receive stream in heal mode to trigger the flaw.
Potential Impact
Successful exploitation results in kernel memory corruption, which could lead to system instability or potential privilege escalation. However, exploitation requires local user access with specific ZFS permissions, limiting the attack surface.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict local user permissions to prevent unauthorized use of the 'receive' delegated ZFS permission.
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… (CVE-2026-49430)
Description
A vulnerability exists in the ZFS_IOC_RECV_NEW ioctl in the heal receive path where a 64-bit payload size is truncated to a 32-bit integer for allocation but the original 64-bit size is used for a byteswap operation. This flaw allows a local user with delegated ZFS receive permission to cause kernel memory corruption by sending a specially crafted receive stream in heal mode.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The ZFS_IOC_RECV_NEW ioctl in the ZFS filesystem's heal receive path improperly truncates a 64-bit payload size to a 32-bit integer when allocating memory, but subsequently uses the original 64-bit size for a byteswap operation. This mismatch can lead to kernel memory corruption. Exploitation requires local access with the delegated 'receive' ZFS permission and involves sending a crafted receive stream in heal mode to trigger the flaw.
Potential Impact
Successful exploitation results in kernel memory corruption, which could lead to system instability or potential privilege escalation. However, exploitation requires local user access with specific ZFS permissions, limiting the attack surface.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict local user permissions to prevent unauthorized use of the 'receive' delegated ZFS permission.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-gx22-rr34-hq5j
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-49430"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a85b4b4acd9273b49251599
Added to database: 08/19/2026, 13:50:44 UTC
Last enriched: 08/19/2026, 14:20:23 UTC
Last updated: 08/19/2026, 14:20:23 UTC
Views: 2
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