# CVE-2026-64006: netfilter: nf_tables: fix dst corruption in same register operation

> A logic error in Linux kernel netfilter shift operations causes memory corruption when source and destination registers overlap, potentially allowing local privilege escalation.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jul 2026
- **Updated:** 21 Oct 2026
- **Also known as:** BELL-CVE-2026-64006, DEBIAN-CVE-2026-64006, GHSA-hwcj-9qvc-gc7f, ROOT-OS-DEBIAN-11-CVE-2026-64006, ROOT-OS-DEBIAN-12-CVE-2026-64006, ROOT-OS-UBUNTU-2204-CVE-2026-64006, UBUNTU-CVE-2026-64006

## What is CVE-2026-64006?

CVE-2026-64006 is a medium-severity memory corruption vulnerability in Linux kernel, published on 19 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_tables: fix dst corruption in same register operation

For lshift and rshift, the shift operations are performed in a loop over
32-bit words. The loop calculates the shifted value and write it to dst,
and then immediately reads from src to calculate the carry for the next
iteration. Because src and dst could point to the same memory location,
the carry is incorrectly calculated using the newly modified dst value
instead of the original src value.

Adding a temporary local variable to cache the original value before
writing to dst and using it for the carry calculation solves the
problem. In addition, partial overlap is rejected from control plane for
all kind of operations including byteorder. This was tested with the
following bytecode:

table test_table ip flags 0 use 1 handle 1
ip test_table test_chain use 3 type filter hook input prio 0 policy accept packets 0 bytes 0 flags 1
ip test_table test_chain 2
  [ immediate reg 1 0x44332211 0x88776655 ]
  [ bitwise reg 1 = ( reg 1 << 0x08000000 ) ]
  [ cmp eq reg 1 0x66443322 0x00887766 ]
  [ counter pkts 0 bytes 0 ]
ip test_table test_chain 4 3
  [ immediate reg 1 0x44332211 0x88776655 ]
  [ bitwise reg 1 = ( reg 1 << 0x08000000 ) ]
  [ cmp eq reg 1 0x55443322 0x00887766 ]
  [ counter pkts 21794 bytes 1917798 ]

Weakness: CWE-682 (Incorrect Calculation)

## Which versions are affected by CVE-2026-64006?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64006?

Apply the vendor's patch.

## Is CVE-2026-64006 being exploited?

There is no known exploitation of CVE-2026-64006 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64006 and fix it if it is affected.

What it is: CVE-2026-64006 is a medium-severity memory corruption vulnerability in Linux kernel, published on 19 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-64006 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-64006/ (Markdown: https://insights.sbomify.com/CVE-2026-64006/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64006
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64006
- OSV: https://osv.dev/vulnerability/CVE-2026-64006

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64006/
Summaries are generated and may contain mistakes; the official description above is the record.