CVE-2026-63972 net: mana: Skip redundant detach on already-detached port

What is CVE-2026-63972?

CVE-2026-63972 is a high-severity vulnerability in Linux kernel, published on 19 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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

net: mana: Skip redundant detach on already-detached port

When mana_per_port_queue_reset_work_handler() runs after a previous detach succeeded but attach failed, the port is left in a detached state with apc->tx_qp and apc->rxqs already freed. Calling mana_detach() again unconditionally leads to NULL pointer dereferences during queue teardown.

Add an early exit in mana_detach() when the port is already in detached state (!netif_device_present) for non-close callers, making it safe to call idempotently. This allows the queue reset handler and other recovery paths to simply retry mana_attach() without redundant teardown.

Weakness: CWE-476

Which versions are affected by CVE-2026-63972?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-63972?

Apply the vendor's patch.

Is CVE-2026-63972 being exploited?

There is no known exploitation of CVE-2026-63972 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-63972, DEBIAN-CVE-2026-63972, GHSA-h62q-3pmg-9366, UBUNTU-CVE-2026-63972.