CVE-2026-45998 Linux CVE debrief

Who should care

Linux kernel maintainers, users, and system administrators should assess exposure and prioritize patching, especially for systems using rxrpc. This includes operators, platform administrators, vulnerability management teams, and security teams. They should review and apply patches for Linux kernel versions 6.2 through 7.0.4 and monitor systems for potential crashes.

Why it matters

A use-after-free vulnerability in the Linux kernel's rxrpc subsystem has been addressed. Linux kernel maintainers and users should assess exposure and prioritize patching.

• Potential system crashes when `trace_rxrpc_rx_done()` is called
• Need to verify and apply patches for Linux kernel versions 6.2 through 7.0.4
• Possible data loss or corruption due to use-after-free issue

Technical summary

The vulnerability is a use-after-free issue in the rxrpc subsystem of the Linux kernel. It occurs when skb_unshare() fails to unshare a packet due to allocation failure in rxrpc_input_packet(). The fix moves the unsharing down to where rxrpc_input_call_event() calls rxrpc_input_call_packet(). This change prevents potential crashes when trace_rxrpc_rx_done() is called. Linux kernel maintainers and users should assess exposure and prioritize patching, especially for systems using rxrpc. The CVE record and NVD entry provide details on the vulnerability and its patches.

Defensive priority

Linux kernel maintainers and users should assess exposure and prioritize patching, especially for systems using rxrpc.

Recommended defensive actions

• Assess exposure and prioritize patching for Linux kernel versions 6.2 through 7.0.4
• Review and apply patches from Linux kernel repository
• Monitor systems using rxrpc for potential crashes
• Verify affected product deployments exist in managed environments
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD entry provide details on the vulnerability and its patches. Multiple patch links are available, including those from the Linux kernel repository. Linux kernel maintainers and users should verify and apply patches for Linux kernel versions 6.2 through 7.0.4. The vulnerability has been resolved in later kernel versions. Users should assess exposure and prioritize patching, especially for systems using rxrpc. The fix involves moving the unsharing down to where rxrpc_input_call_event() calls rxrpc_input_call_packet.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.