Description
In the Linux kernel, the following vulnerability has been resolved:
USB: serial: cypress_m8: validate interrupt packet headers
cypress_read_int_callback() parses the interrupt-in buffer according to
the selected Cypress packet format. Format 1 has a two-byte status/count
header and format 2 has a one-byte combined status/count header. The
usb-serial core sizes the interrupt-in buffer from the endpoint
descriptor's wMaxPacketSize, and successful interrupt transfers can
complete short when URB_SHORT_NOT_OK is not set.
Check that the completed packet contains the selected header before
reading it. Malformed short reports are ignored and the interrupt URB is
resubmitted through the existing retry path, preventing out-of-bounds
header-byte reads.
KASAN report as below:
KASAN slab-out-of-bounds in cypress_read_int_callback+0x240/0x7f0
Read of size 1
Call trace:
cypress_read_int_callback() (drivers/usb/serial/cypress_m8.c:1009)
__usb_hcd_giveback_urb()
dummy_timer()
[ johan: use constants in header length sanity checks ]
USB: serial: cypress_m8: validate interrupt packet headers
cypress_read_int_callback() parses the interrupt-in buffer according to
the selected Cypress packet format. Format 1 has a two-byte status/count
header and format 2 has a one-byte combined status/count header. The
usb-serial core sizes the interrupt-in buffer from the endpoint
descriptor's wMaxPacketSize, and successful interrupt transfers can
complete short when URB_SHORT_NOT_OK is not set.
Check that the completed packet contains the selected header before
reading it. Malformed short reports are ignored and the interrupt URB is
resubmitted through the existing retry path, preventing out-of-bounds
header-byte reads.
KASAN report as below:
KASAN slab-out-of-bounds in cypress_read_int_callback+0x240/0x7f0
Read of size 1
Call trace:
cypress_read_int_callback() (drivers/usb/serial/cypress_m8.c:1009)
__usb_hcd_giveback_urb()
dummy_timer()
[ johan: use constants in header length sanity checks ]
Published:
2026-07-19
Score:
n/a
EPSS:
< 1% Very Low
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
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References
History
Sun, 19 Jul 2026 15:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: USB: serial: cypress_m8: validate interrupt packet headers cypress_read_int_callback() parses the interrupt-in buffer according to the selected Cypress packet format. Format 1 has a two-byte status/count header and format 2 has a one-byte combined status/count header. The usb-serial core sizes the interrupt-in buffer from the endpoint descriptor's wMaxPacketSize, and successful interrupt transfers can complete short when URB_SHORT_NOT_OK is not set. Check that the completed packet contains the selected header before reading it. Malformed short reports are ignored and the interrupt URB is resubmitted through the existing retry path, preventing out-of-bounds header-byte reads. KASAN report as below: KASAN slab-out-of-bounds in cypress_read_int_callback+0x240/0x7f0 Read of size 1 Call trace: cypress_read_int_callback() (drivers/usb/serial/cypress_m8.c:1009) __usb_hcd_giveback_urb() dummy_timer() [ johan: use constants in header length sanity checks ] | |
| Title | USB: serial: cypress_m8: validate interrupt packet headers | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-07-19T14:55:10.267Z
Reserved: 2026-07-19T07:54:57.019Z
Link: CVE-2026-63902
Vulnrichment
No data.
NVD
No data.
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.