CVE-2026-53007: Linux ice Driver NULL Pointer Dereference Denial of Service

Technical summary

CVE-2026-53007 is a NULL pointer dereference in ice_set_ringparam() within the Linux kernel ice driver (Intel Ethernet Controller driver). The vulnerability arises when ice_set_ringparam() nullifies the tstamp_ring member of temporary tx_rings without clearing the ICE_TX_RING_FLAGS_TXTIME bit. If ice_setup_tx_ring() subsequently fails, the error unwinding path calls ice_clean_tx_ring(), which checks the ICE_TX_RING_FLAGS_TXTIME flag. Since the flag remains set while tstamp_ring is NULL, ice_free_tx_tstamp_ring() → ice_free_tstamp_ring() dereferences a NULL pointer when accessing tstamp_ring->desc, triggering a kernel panic. The root cause is missing flag cleanup during ring parameter initialization. CWE-476 (NULL pointer dereference).

Business impact

This vulnerability permits denial of service via kernel panic on systems running affected Linux kernel versions with the ice driver loaded. A local attacker with standard user privileges can crash the host by manipulating transmit ring configuration, disrupting services, requiring system reboot, and potentially enabling follow-on attacks. For organizations running Intel-based Ethernet controllers (E830 devices and compatible hardware) in production environments, this represents availability risk requiring kernel patching during maintenance windows.

Affected systems

Linux kernel systems equipped with Intel ice Ethernet driver. Vulnerability requires the ice driver to be active and accessible to local users. E830 devices and compatible Intel Ethernet controllers are the primary hardware targets, though the driver may be present on other systems. The issue is specific to the kernel-space driver component and affects systems where ice is compiled in or loaded as a module.

Exploitability

Exploitability is moderate in scope but limited in access. The vulnerability requires local system access (AV:L), no special privileges beyond standard user level (PR:L), no user interaction, and causes availability impact only (no confidentiality or integrity). An unprivileged local user can trigger a kernel crash via ring parameter manipulation, making this practical for local denial of service. Remote exploitation is not possible. The attack surface is limited to systems where the ice driver is actively used and locally accessible.

Remediation

Apply a Linux kernel security update that includes the fix for CVE-2026-53007. The patch clears the ICE_TX_RING_FLAGS_TXTIME bit during ice_set_ringparam() execution to ensure consistent state between the flag and the underlying tstamp_ring pointer. Verify the patched kernel version against your distribution's advisory. For systems using Intel E830 or compatible controllers with ice driver loaded, prioritize testing and deployment of the patched kernel during the next maintenance window. No workaround is available without a kernel patch.

Patch guidance

Monitor your Linux distribution's security advisory channels for kernel updates addressing CVE-2026-53007. Verify the patch version and release notes against your vendor's security bulletin. Kernel patches typically require reboot to take effect. Test the patched kernel in a non-production environment first to ensure driver stability and compatibility with your network stack configuration. Document the patch application date and kernel version for compliance tracking. Note that the original vulnerability discovery was via code review and compile testing, so field validation may be ongoing—coordinate with your vendor on any post-patch monitoring recommendations.

Detection guidance

Monitor kernel logs for ice driver oops or panic messages associated with tstamp_ring operations or ice_set_ringparam(). Detection tools: kernel crash dumps (kdump), syslog aggregation with pattern matching on 'ice_free_tstamp_ring' or 'NULL pointer dereference', and eBPF-based syscall monitoring to detect unusual transmit ring parameter changes. On systems running affected kernels, enable verbose kernel logging and monitor for ice driver crashes. However, note that this is a local denial-of-service vector; successful exploitation will be obvious as kernel panic events.

Why prioritize this

Assign medium-to-high priority based on local-only access requirements and denial-of-service impact. Systems running Intel ice driver should patch promptly to prevent availability disruption. Prioritize production systems and those with untrusted local users. The CVSS 5.5 (MEDIUM) reflects limited attack surface (local only) and availability-only impact, but organizations with high-availability requirements should treat this as urgent to prevent unexpected downtime.

Risk score, explained

CVSS 3.1 score of 5.5 (MEDIUM) reflects: Attack Vector Local (L) — requires direct system access; Attack Complexity Low (L) — no special conditions needed; Privileges Required Low (L) — standard user access sufficient; User Interaction None (N) — automatic trigger; Scope Unchanged (U) — impact limited to the system itself; Confidentiality None (N); Integrity None (N); Availability High (A) — kernel panic disables the system. The score appropriately weights the denial-of-service impact against the local-only access requirement. For organizations with strict uptime requirements, risk tolerance may warrant treating this as high-priority despite the medium CVSS.

Frequently asked questions