CVE-2022-48958

What it actually does

Potential socket buffer (skb) memory leak in greth_init_rings() when dma_mapping_error() returns an error, leaving the newly allocated skb unfreed.

Why it matters to the business

Gradual memory exhaustion on systems using the affected Aeroflex GRETH Ethernet driver, leading to degraded network performance or system instability in long-running environments; low overall risk given limited exploit maturity and no known in-the-wild use.

How an attack unfolds

An attacker with the ability to induce DMA mapping failures during driver ring initialization could trigger the leak; no remote unauthenticated path exists under normal conditions, and listed threat actor campaigns have not been tied to this specific flaw.

How to fix it

Apply the kernel fix that adds dev_kfree_skb() on DMA mapping error in greth_init_rings(); for the referenced mediawiki-skins-citizen component, update to commit 717d16af35b10dab04d434aefddbf991fc8c168c or later.

How to confirm the fix worked

Confirm the presence of the dev_kfree_skb() call after the dma_mapping_error() check in greth_init_rings(); review kernel build logs or driver source for the corrected allocation path.

Typical attack path

1. Locate a system running a vulnerable Linux kernel with the Aeroflex GRETH driver enabled
2. Trigger conditions that cause dma_mapping_error() to fail during greth_init_rings()
3. Repeat to accumulate leaked skb buffers
4. Monitor for memory pressure or crashes

How to detect it

Search kernel logs and driver initialization traces for repeated greth ring setup failures without corresponding skb frees; monitor memory usage trends on systems exposing the Aeroflex GRETH interface.

What your security team should do

• Prioritize patching systems that use the Aeroflex GRETH driver in production network stacks
• Monitor EPSS and KEV updates for any change in exploitation likelihood
• Audit custom or embedded Linux builds that include the greth driver