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CVE-2025-21916

Description

In the Linux kernel, the following vulnerability has been resolved:usb: atm: cxacru: fix a flaw in existing endpoint checksSyzbot once again identified a flaw in usb endpoint checking, see [1].This time the issue stems from a commit authored by me (2eabb655a968("usb: atm: cxacru: fix endpoint checking in cxacru_bind()")).While using usb_find_common_endpoints() may usually be enough todiscard devices with wrong endpoints, in this case one needs morethan just finding and identifying the sufficient number of endpointsof correct types - one needs to check the endpoint's address as well.Since cxacru_bind() fills URBs with CXACRU_EP_CMD address in mind,switch the endpoint verification approach to usb_check_XXX_endpoints()instead to fix incomplete ep testing.[1] Syzbot report:usb 5-1: BOGUS urb xfer, pipe 3 != type 1WARNING: CPU: 0 PID: 1378 at drivers/usb/core/urb.c:504 usb_submit_urb+0xc4e/0x18c0 drivers/usb/core/urb.c:503...RIP: 0010:usb_submit_urb+0xc4e/0x18c0 drivers/usb/core/urb.c:503...Call Trace: cxacru_cm+0x3c8/0xe50 drivers/usb/atm/cxacru.c:649 cxacru_card_status drivers/usb/atm/cxacru.c:760 [inline] cxacru_bind+0xcf9/0x1150 drivers/usb/atm/cxacru.c:1223 usbatm_usb_probe+0x314/0x1d30 drivers/usb/atm/usbatm.c:1058 cxacru_usb_probe+0x184/0x220 drivers/usb/atm/cxacru.c:1377 usb_probe_interface+0x641/0xbb0 drivers/usb/core/driver.c:396 really_probe+0x2b9/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830...

POC

Reference

No PoCs from references.

Github

- https://github.com/ARPSyndicate/cve-scores

- https://github.com/w4zu/Debian_security