cbcvebase.
CVE-2026-31607
published 2026-04-24

CVE-2026-31607: In the Linux kernel, the following vulnerability has been resolved: usbip: validate number_of_packets in usbip_pack_ret_submit() When a USB/IP client receives…

PriorityP357critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.31%
23.4th percentile
In the Linux kernel, the following vulnerability has been resolved: usbip: validate number_of_packets in usbip_pack_ret_submit() When a USB/IP client receives a RET_SUBMIT response, usbip_pack_ret_submit() unconditionally overwrites urb->number_of_packets from the network PDU. This value is subsequently used as the loop bound in usbip_recv_iso() and usbip_pad_iso() to iterate over urb->iso_frame_desc[], a flexible array whose size was fixed at URB allocation time based on the *original* number_of_packets from the CMD_SUBMIT. A malicious USB/IP server can set number_of_packets in the response to a value larger than what was originally submitted, causing a heap out-of-bounds write when usbip_recv_iso() writes to urb->iso_frame_desc[i] beyond the allocated region. KASAN confirmed this with kernel 7.0.0-rc5: BUG: KASAN: slab-out-of-bounds in usbip_recv_iso+0x46a/0x640 Write of size 4 at addr ffff888106351d40 by task vhci_rx/69 The buggy address is located 0 bytes to the right of allocated 320-byte region [ffff888106351c00, ffff888106351d40) The server side (stub_rx.c) and gadget side (vudc_rx.c) already validate number_of_packets in the CMD_SUBMIT path since commits c6688ef9f297 ("usbip: fix stub_rx: harden CMD_SUBMIT path to handle malicious input") and b78d830f0049 ("usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input"). The server side validates against USBIP_MAX_ISO_PACKETS because no URB exists yet at that point. On the client side we have the original URB, so we can use the tighter bound: the response must not exceed the original number_of_packets. This mirrors the existing validation of actual_length against transfer_buffer_length in usbip_recv_xbuff(), which checks the response value against the original allocation size. Kelvin Mbogo's series ("usb: usbip: fix integer overflow in usbip_recv_iso()", v2) hardens the receive-side functions themselves; this patch complements that work by catching the bad value at its source -- in usbip_pack

Affected

75 ranges· showing 25
VendorProductVersion rangeFixed in
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 324262c38438255bf6bdbf6342ca47c0badaab76324262c38438255bf6bdbf6342ca47c0badaab76
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 973f2c250289f5bf6cc146b98aa6fdde11fe50d6973f2c250289f5bf6cc146b98aa6fdde11fe50d6
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < ce744264b06b97069b3722511ab355738311fee0ce744264b06b97069b3722511ab355738311fee0
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 885c8591784da6314f9aa82fa460ac69f9f79e5f885c8591784da6314f9aa82fa460ac69f9f79e5f
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 8d155e2d1c4102f74f82a2bf9c016164bb0f73848d155e2d1c4102f74f82a2bf9c016164bb0f7384
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 906f16a836de13fe61f49cdce2f66f2dbd14caf4906f16a836de13fe61f49cdce2f66f2dbd14caf4
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < ef8ebb1c637b4cfb61a9dd2e013376774ee2033bef8ebb1c637b4cfb61a9dd2e013376774ee2033b
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 5e1c4ece08ccdc197177631f111845a2c68eede35e1c4ece08ccdc197177631f111845a2c68eede3
linuxlinux>= 1325f85fa49f57df034869de430f7c302ae23109 < 2ab833a16a825373aad2ba7d54b572b277e95b712ab833a16a825373aad2ba7d54b572b277e95b71
linuxlinux>= 2.6.32.37 < 2.6.332.6.33
linuxlinux>= 2.6.33.10 < 2.6.342.6.34
linuxlinux>= 2.6.34.11 < 2.6.352.6.35
linuxlinux>= 2.6.35.13 < 2.6.362.6.36
linuxlinux>= 2.6.38.3 < 2.6.392.6.39
linuxlinux_kernel
linuxlinux_kernel>= 2.6.39 < 6.6.1366.6.136
linuxlinux_kernel>= 6.13 < 6.18.246.18.24
linuxlinux_kernel>= 6.19 < 6.19.146.19.14
linuxlinux_kernel>= 6.7 < 6.12.836.12.83

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_ubuntu8.8HIGH
vendor_redhat7.0HIGH
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