# CVE-2026-64545: Linux Kernel NULL pointer dereference in xdp_master_redirect

Source: https://junglewise.ai/threats/cve-2026-64545-linux-kernel-null-pointer-dereference-in-xdp-master-redirect  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-27. Updated: 2026-07-27  
License: CC BY 4.0 with a link back

CVE-2026-64545 · Severity: info · CVSS 6.2 · Published 2026-07-27

A vulnerability in the Linux kernel's networking component could allow a remote attacker to cause a system crash (kernel panic). This occurs when specific network traffic is processed while a network interface is being disconnected from a 'bonded' group. This issue primarily impacts system availability and could lead to service outages.

Technologies: [Linux Kernel](https://junglewise.ai/threats/technologies/kernel). Vendors: [Linux](https://junglewise.ai/threats/vendors/linux).

## Quick answers

**Is CVE-2026-64545 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-64545 being exploited in the wild.

**How severe is CVE-2026-64545?** Informational severity, with a CVSS score of 6.2, published 27 July 2026.

**Which products and versions are affected?** Linux Kernel 879af96ffd72 to e82d8cc4321c.

**Is there a fix for CVE-2026-64545?** A patch was published on 2026-07-24: Commits merged into stable branches Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-64545 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2026-64545?** Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A NULL pointer dereference exists in net/core/filter.c within the xdp_master_redirect() function. The vulnerability is caused by a race condition during the release of a bond slave; bond_upper_dev_unlink() removes the upper-master adjacency before the IFF_SLAVE flag is cleared. If an XDP_TX event occurs during this window, xdp_master_redirect() attempts to dereference the 'master' pointer returned by netdev_master_upper_dev_get_rcu() without a NULL check. This results in a kernel panic when the code attempts to read master->flags. The fix introduces a NULL check for the master device before dereferencing.

## Affected products

- Linux Linux Kernel 879af96ffd72 to e82d8cc4321c

## Timeline

- 2026-06-20: disclosed: Initial patch submitted by Xiang Mei
- 2026-07-24: patched: Commits merged into stable branches
- 2026-07-27: advisory: CVE-2026-64545 published

## References

- [https://git.kernel.org/stable/c/03b743586a2469744e96e9c1015096d07240935d](https://git.kernel.org/stable/c/03b743586a2469744e96e9c1015096d07240935d)
- [https://git.kernel.org/stable/c/3876318ea54e83eb70982b8280a3c5e4e32269bf](https://git.kernel.org/stable/c/3876318ea54e83eb70982b8280a3c5e4e32269bf)
- [https://git.kernel.org/stable/c/4edbcacca09f92b85d3951b6add11894b20a84bc](https://git.kernel.org/stable/c/4edbcacca09f92b85d3951b6add11894b20a84bc)
- [https://git.kernel.org/stable/c/89c103d702b25ceb2d097faf854deb47b53b17ff](https://git.kernel.org/stable/c/89c103d702b25ceb2d097faf854deb47b53b17ff)
- [https://git.kernel.org/stable/c/c99ca049e910d61ddbd28cc2c47242f2bfbb4970](https://git.kernel.org/stable/c/c99ca049e910d61ddbd28cc2c47242f2bfbb4970)
- [https://git.kernel.org/stable/c/e2a56441233131fe18a76001de347ecda217e40c](https://git.kernel.org/stable/c/e2a56441233131fe18a76001de347ecda217e40c)
- [https://git.kernel.org/stable/c/e82d8cc4321c373dc46e741cd2dfdaa7921fddb7](https://git.kernel.org/stable/c/e82d8cc4321c373dc46e741cd2dfdaa7921fddb7)

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