CVE-2026-46101: netfilter: reject zero shift in nft_bitwise
In the Linux kernel, the following vulnerability has been resolved:
netfilter: reject zero shift in nftbitwise
Reject zero shift operands for nftbitwise left and right shift expressions during initialization.
The carry propagation logic computes the carry from the adjacent 32-bit word using BITSPERTYPE(u32) - shift. A zero shift operand turns this into a 32-bit shift, which is undefined behaviour.
Reject zero shift operands in the control plane, alongside the existing check for values greater than or equal to 32, so malformed rules never reach the packet path.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.141.1-1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-46101?
CVE-2026-46101 has a risk rating of 37.
How do I fix CVE-2026-46101?
To fix CVE-2026-46101, update to the latest version of the Linux kernel that addresses this vulnerability.
What systems are affected by CVE-2026-46101?
CVE-2026-46101 affects Linux kernel implementations that utilize the netfilter nft_bitwise functionality.
What kind of vulnerability is CVE-2026-46101?
CVE-2026-46101 is a programming error related to rejecting zero shift operands in bitwise shift operations.
When was CVE-2026-46101 published?
CVE-2026-46101 was published on May 27, 2026.