Description (CNA)
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_ret_submit() before the overwrite -- and using the tighter per-URB allocation bound rather than the global USBIP_MAX_ISO_PACKETS limit. Fix this by checking rpdu->number_of_packets against urb->number_of_packets in usbip_pack_ret_submit() before the overwrite. On violation, clamp to zero so that usbip_recv_iso() and usbip_pad_iso() safely return early.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 1325f85fa49f57df034869de430f7c302ae23109 before 324262c38438255bf6bdbf6342ca47c0badaab76; affected 1325f85fa49f57df034869de430f7c302ae23109 before 973f2c250289f5bf6cc146b98aa6fdde11fe50d6; affected 1325f85fa49f57df034869de430f7c302ae23109 before ce744264b06b97069b3722511ab355738311fee0; affected 1325f85fa49f57df034869de430f7c302ae23109 before 885c8591784da6314f9aa82fa460ac69f9f79e5f; affected 1325f85fa49f57df034869de430f7c302ae23109 before 8d155e2d1c4102f74f82a2bf9c016164bb0f7384; affected 1325f85fa49f57df034869de430f7c302ae23109 before 906f16a836de13fe61f49cdce2f66f2dbd14caf4; affected 1325f85fa49f57df034869de430f7c302ae23109 before ef8ebb1c637b4cfb61a9dd2e013376774ee2033b; affected 1325f85fa49f57df034869de430f7c302ae23109 before 5e1c4ece08ccdc197177631f111845a2c68eede3; affected 1325f85fa49f57df034869de430f7c302ae23109 before 2ab833a16a825373aad2ba7d54b572b277e95b71; affected d9638d9236eed035a575feddec61d036dacc2676; affected ca7d3501b7a287c18b5b470e871d3029b0f4842a; affected 1ce528277e1a66856ed3f7526c1e3458c0ed4a70; affected db898d0c5c493ce4177d5e1d3a953e079a56a24b; affected 5aa02704b9ee67c5b2ee26d54c5f4eb99e93ba9a; affected 2.6.32.37 before 2.6.33; affected 2.6.33.10 before 2.6.34; affected 2.6.34.11 before 2.6.35; affected 2.6.35.13 before 2.6.36; affected 2.6.38.3 before 2.6.39 |
| Linux / Linux | affected 2.6.39; unaffected 0 before 2.6.39; unaffected 5.10.258 through 5.10.*; unaffected 5.15.209 through 5.15.*; unaffected 6.1.175 through 6.1.*; unaffected 6.6.136 through 6.6.*; unaffected 6.12.83 through 6.12.*; unaffected 6.18.24 through 6.18.*; unaffected 6.19.14 through 6.19.*; unaffected 7.0.1 through 7.0.*; unaffected 7.1 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/324262c38438255bf6bdbf6342ca47c0badaab76
- https://git.kernel.org/stable/c/973f2c250289f5bf6cc146b98aa6fdde11fe50d6
- https://git.kernel.org/stable/c/ce744264b06b97069b3722511ab355738311fee0
- https://git.kernel.org/stable/c/885c8591784da6314f9aa82fa460ac69f9f79e5f
- https://git.kernel.org/stable/c/8d155e2d1c4102f74f82a2bf9c016164bb0f7384
- https://git.kernel.org/stable/c/906f16a836de13fe61f49cdce2f66f2dbd14caf4
- https://git.kernel.org/stable/c/ef8ebb1c637b4cfb61a9dd2e013376774ee2033b
- https://git.kernel.org/stable/c/5e1c4ece08ccdc197177631f111845a2c68eede3
- https://git.kernel.org/stable/c/2ab833a16a825373aad2ba7d54b572b277e95b71
ADP enrichment
A flaw was found in the Linux kernel's USB/IP subsystem. A malicious USB/IP server could exploit a vulnerability in the `usbip_pack_ret_submit()` function by sending a specially crafted `RET_SUBMIT` response. This response, containing an oversized `number_of_packets` value, could cause a heap out-of-bounds write. This issue may lead to a denial of service or potentially arbitrary code execution on the client system.
- https://access.redhat.com/security/cve/CVE-2026-31607
- https://bugzilla.redhat.com/show_bug.cgi?id=2461521
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31607.json
- https://access.redhat.com/errata/RHSA-2026:25095
- https://access.redhat.com/errata/RHSA-2026:41236
- https://access.redhat.com/errata/RHSA-2026:24343
- https://access.redhat.com/errata/RHSA-2026:19569
- https://access.redhat.com/errata/RHSA-2026:23224
- https://access.redhat.com/errata/RHSA-2026:19568
No English description supplied.
No references supplied.