{"cve":"CVE-2026-98025","nvd":{"published":"2026-09-25T11:17:31.110","modified":"2026-10-19T10:17:56.440","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: usb: cx82310_eth: drop URB after 0xffff reboot sentinel to prevent partial_data heap overflow\n\nThe 0xffff length sentinel detects a router reboot and schedules\nre-enabling of ethernet mode, but then falls through to the rest\nof the loop body.  The next check is\n\n\t} else if (len > CX82310_MTU) {\n\nwhich is the else of the just-matched if -- it never fires for\nlen == 0xffff.  The MTU bound that normally caps the\nincomplete-packet save path is silently bypassed.\n\nWith 0xffff > skb->len always true (rx_urb_size is 4096), the\nincomplete-packet branch saves dev->partial_len = skb->len bytes\ninto dev->partial_data.  partial_data is kmalloc(hard_mtu) =\nkmalloc(CX82310_MTU + 2) = 1516 bytes, but skb->len after the\n2-byte header pull can be up to 4094.  A device that sends a\n4096-byte URB starting with [0xff 0xff] therefore copies 4094\ndevice-provided bytes into a buffer allocated for 1516 bytes,\nexceeding its requested size by 2578 bytes.\n\nThe next URB then reads dev->partial_len (4094) back from the same\n1516-byte buffer and dev->partial_rem (65535 - 4094 = 61441) from\nthe new URB's ~4KB skb, both well past their allocations, and\ndelivers the spliced result as a 64KB \"frame\" to the network\nstack.\n\nBail out of rx_fixup after scheduling the re-enable work; the\nremainder of a reboot-marker URB is not meaningful packet data.\nThis restores the invariant that partial_len < CX82310_MTU + 2 on\nthe save path, since every other route there has already passed\nthe MTU check.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/00520cdd21ea6a9b5dc8d53bbd241620d2059554","https://git.kernel.org/stable/c/0dbc89e664b4609ad672b5bdeef60df251294b8f","https://git.kernel.org/stable/c/237c9ae7145772af147e4665f158938350fa5658","https://git.kernel.org/stable/c/3bd689409bb1c93bdc6dd8ec6cbf5161bc4f0287","https://git.kernel.org/stable/c/59bf9e94bdc49557f07d87164269daff7340f4d6"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:02.509636177+00:00"},"epss":{"cve":"CVE-2026-98025","score":0.00231,"percentile":0.13764,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}