Skip to main content

Linux Kernel EUVDEUVD-2026-45745

| CVE-2026-63972 HIGH
2026-07-19 Linux GHSA-h62q-3pmg-9366
7.5
CVSS 3.1 · Vendor: Linux
Share

Severity by source

Vendor (Linux) PRIMARY
7.5 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vuln.today AI
4.7 MEDIUM

Crash arises from an internal MANA attach-failure recovery state, not remote packets, so AV:L and AC:H; some local privilege/device control is needed (PR:L) and impact is availability-only.

3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
4.0 AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SUSE
HIGH
qualitative

Primary rating from Vendor (Linux).

CVSS VectorVendor: Linux

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

5
Analysis Generated
Jul 20, 2026 - 16:35 vuln.today
CVSS changed
Jul 20, 2026 - 15:22 NVD
7.5 (HIGH)
Patch available
Jul 19, 2026 - 17:19 EUVD
CVE Published
Jul 19, 2026 - 14:55 cve.org
HIGH 7.5
CVE Published
Jul 19, 2026 - 14:55 cve.org
UNKNOWN (no severity yet)

DescriptionCVE.org

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.

AnalysisAI

Denial of service in the Linux kernel MANA (Microsoft Azure Network Adapter) Ethernet driver allows the port reset recovery path to trigger a NULL pointer dereference and kernel crash. The flaw occurs when mana_per_port_queue_reset_work_handler() runs after a prior detach succeeded but a subsequent attach failed, leaving apc->tx_qp and apc->rxqs freed; a second unconditional mana_detach() then dereferences NULL during queue teardown. No public exploit has been identified, EPSS is low (0.20%, 10th percentile), and the CVSS 3.1 score is 7.5 driven purely by availability impact.

Technical ContextAI

The affected component is the MANA driver (drivers/net/ethernet/microsoft/mana) which provides networking for Linux guests running on Microsoft Azure using the Azure Network Adapter virtual hardware. The root cause is a NULL pointer dereference (CWE-476, though the feed lists CWE as N/A) in the port recovery state machine: after a detach frees the transmit queue pairs (tx_qp) and receive queues (rxqs), a failed re-attach leaves the port in a detached state (!netif_device_present), and calling mana_detach() again walks structures that have already been freed. The fix adds an idempotency guard - an early exit in mana_detach() when the port is already detached for non-close callers - so recovery paths such as the queue reset handler can safely retry mana_attach() without redundant teardown. The CPE data (cpe:2.3:a:linux:linux) is generic to the kernel and does not narrow to the driver, but the code path is exclusive to Azure MANA-backed interfaces.

RemediationAI

Vendor-released patch: upgrade to Linux 6.18.35 or later (or the corresponding fixed 7.0.x/7.1 build for those trees), which adds the idempotency guard in mana_detach(). Apply the stable fix commits from https://git.kernel.org/stable/c/c4152b4e28b3e550ec99351bf900e2c24c2608cc (and companions 7ae590797f9b5c240aaea5773f5f00977a42a846 and 5b05aa36ee24297d7296ca58dfd8c448d0e4cda3) if backporting to a custom kernel. For Azure guest fleets, follow your distribution's kernel update channel (the fix will flow into Azure-tuned kernel images). No practical pre-patch workaround exists because the crash originates in the driver's internal recovery path rather than a toggleable feature; the only compensating control is operational - monitor for and reduce MANA interface attach failures (e.g. avoid churn that induces port detach/re-attach cycles) and ensure host/VM live-migration and NIC hotplug events are stable, accepting that this only reduces, not eliminates, the trigger condition.

Vendor StatusVendor

SUSE

Severity: Important
Product Status
SUSE Linux Enterprise Desktop 15 SP7 Affected
SUSE Linux Enterprise Desktop 15 SP7 Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Affected
SUSE Linux Enterprise High Availability Extension 16.0 Affected

Share

EUVD-2026-45745 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy