{"id":"CVE-2026-63960","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-63960","generatedAt":"2026-10-28T00:28:34.309Z","title":"In the Linux kernel, the following vulnerability has been resolved: usb: typec: wcove: don't write past struct pd_message in wcove_read_rx_buffer() wcove_read_rx_buffer() copies the PD RX FIFO into the caller's struct pd_message with for (i = 0; i <…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: typec: wcove: don't write past struct pd_message in wcove_read_rx_buffer()\n\nwcove_read_rx_buffer() copies the PD RX FIFO into the caller's\nstruct pd_message with\n\n\tfor (i = 0; i < USBC_RXINFO_RXBYTES(info); i++)\n\t\tregmap_read(wcove->regmap, USBC_RX_DATA + i, msg + i);\n\nwhich has two problems:\n\nUSBC_RXINFO_RXBYTES() is a 5-bit field (max 31) while struct pd_message\nis 30 bytes (__le16 header + __le32 payload[PD_MAX_PAYLOAD], packed).\nThe byte count latched in RXINFO is the number of bytes the port partner\nput on the wire, so a malicious partner that transmits a 31-byte frame\ncan drive the loop one byte past the destination if the WCOVE BMC\nreceiver does not enforce the PD object-count limit in hardware. The\nexisting FIXME flagged this as unverified.\n\nIndependently, regmap_read() takes an unsigned int * and stores a full\nunsigned int at the destination. Passing the byte pointer msg + i means\neach iteration writes four bytes; the high three are zero (val_bits is\n8) and are normally overwritten by the next iteration, but the final\niteration's high bytes are not. With RXBYTES == 30 the i == 29 iteration\nalready writes three zero bytes past msg, which sits on the IRQ thread's\nstack in wcove_typec_irq().\n\nClamp the loop to sizeof(struct pd_message) and read each register into\na local before storing only its low byte, so the copy can never exceed\nthe destination regardless of what RXINFO reports.","published":"2026-07-19T16:17:15.000Z","lastModified":"2026-07-30T14:51:11.000Z","status":"Awaiting Analysis","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":null,"cwe":[],"affected":[],"epss":{"score":0.00211,"percentile":0.11196,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"unknown","text":"Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/3e632098d0521257ea965bbd6fde807d9bee5c8a","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3f9d50c8b02b4af0646aa892465080f9061fc89c","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4af7ad0e6d7aa4403dbb1dac7b9659b0421efcaa","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5cd0e7ac4eefbdb330f8c72694fe74e63df65552","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6899f5b6d7b83ce79a3d331dc61dd31bf73f9c22","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d0e4b8b3c6b7607a16932556eaaca5d5cf69f192","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e94933dc41b87503bf585c8c6d53d740620eceb9","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f2a1edc0bd142edabc6c85d88713f2bc178dd317","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-63960","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}