{"id":"CVE-2026-98492","kind":"vulnerability","aliases":["CVE-2026-98492"],"related":[],"title":"Linux kernel: macb network driver leaks DMA memory on allocation errors","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: macb: fix dma_alloc_coherent() leak on macb_alloc() error paths\n\nFix 3 leaks in macb_alloc() error paths:\n- Tx buffer allocated but crossing a 4G boundary: Tx leaked.\n- Rx buffer allocation fails: Tx leaked.\n- Rx buffer allocated but crossing a 4G boundary: Tx & Rx leaked.\n\nThis is because our error handling calls macb_free(bp) which in turn\nfrees the buffers stored in bp->queues[0], but nothing has been stored\nin there. Fix by storing allocated buffers into bp->queues[0] ASAP.","summary":"In the Linux kernel's Cadence MACB Ethernet driver, error paths in macb_alloc() fail to free DMA-coherent buffers, so memory is leaked when Tx or Rx buffer allocation fails or crosses a 4G boundary. The sources describe a resource leak, not code execution or data exposure.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["arm","embedded","linux-kernel","package"],"not_affected_if":["no-macb-hardware"],"how_to_check":"- unknown","fix":"- Update to a Linux kernel release that includes the upstream commit 'net: macb: fix dma_alloc_coherent() leak on macb_alloc() error paths' (version unknown from sources)","status":"open","published_at":"2026-10-18T16:17:00+00:00","first_seen_at":"2026-10-23T21:57:15+00:00","triaged_at":"2026-10-25T05:25:41+00:00","updated_at":"2026-10-25T05:25:41+00:00","category":"package","confidence":0.5,"triage":{"at":"2026-10-25T05:25:41Z","model":"claude-haiku-5-5","output":{"fix":"- Update to a Linux kernel release that includes the upstream commit 'net: macb: fix dma_alloc_coherent() leak on macb_alloc() error paths' (version unknown from sources)","reach":"local","title":"Linux kernel: macb network driver leaks DMA memory on allocation errors","impact":"low","summary":"In the Linux kernel's Cadence MACB Ethernet driver, error paths in macb_alloc() fail to free DMA-coherent buffers, so memory is leaked when Tx or Rx buffer allocation fails or crosses a 4G boundary. The sources describe a resource leak, not code execution or data exposure.","category":"package","nicknames":[],"who_cares":["linux-kernel","embedded","arm"],"confidence":0.5,"needs_auth":"no","worst_case":"Kernel memory leaks during allocation failures, eventually degrading the system","analyst_note":"","how_to_check":"- unknown","needs_analyst":false,"not_affected_if":["no-macb-hardware"],"who_is_affected":"Systems running a Linux kernel with the Cadence MACB/GEM Ethernet driver, typically certain ARM or embedded boards. The leak only happens when buffer allocation fails or crosses a 4G boundary, so most machines with normal memory conditions are unlikely to hit it. unknown","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000597,"input_tokens":3455,"output_tokens":502,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-98492':14A,17A '0':150C,166C '3':96C '4g':59B,109C,125C 'alloc':10A,37B,54B,87C,92C,100C,105C,115C,121C,161C 'arm':18B 'asap':167C 'boundari':60B,110C,126C 'bp':139C,148C,164C 'buffer':44B,53B,104C,114C,120C,145C,162C 'cadenc':29B 'call':136C 'code':68B 'coher':43B,88C 'cross':57B,107C,123C 'cve':12A,15A 'data':71B 'describ':63B 'dma':7A,42B,86C 'dma-coher':41B 'driver':5A,32B 'embed':19B 'error':11A,33B,93C,101C,134C 'ethernet':31B 'execut':69B 'exposur':72B 'fail':38B,55B,116C 'fix':85C,95C,158C 'follow':78C 'free':40B,138C,143C 'handl':135C 'kernel':2A,22B,27B,76C 'leak':6A,48B,66B,89C,97C,112C,118C,129C 'linux':1A,21B,26B,75C 'linux-kernel':20B 'macb':3A,30B,36B,84C,91C,99C,137C 'memori':8A,46B 'net':83C 'network':4A 'noth':152C 'packag':23B 'path':34B,94C,102C 'queue':149C,165C 'resolv':82C 'resourc':65B 'rx':52B,113C,119C,128C 'sourc':62B 'store':146C,155C,160C 'turn':142C 'tx':50B,103C,111C,117C,127C 'vulner':79C","nicknames":[],"mitigations":[],"who_affected":"Systems running a Linux kernel with the Cadence MACB/GEM Ethernet driver, typically certain ARM or embedded boards. The leak only happens when buffer allocation fails or crosses a 4G boundary, so most machines with normal memory conditions are unlikely to hit it. unknown","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-18T16:17:00+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-98492","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98492","severity":null,"published_at":"2026-10-18T16:17:00+00:00","modified_at":"2026-10-19T10:19:01+00:00","first_seen_at":"2026-10-23T21:57:15+00:00","fetched_at":"2026-10-23T22:28:56+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}