HighFix available

rxrpc: Fix potential UAF after skb_unshare() failure

Type: advisorySources: OSV

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix potential UAF after skb_unshare() failure If skb_unshare() fails to unshare a packet due to allocation failure in rxrpc_input_packet(), the skb pointer in the parent (rxrpc_io_thread()) will be NULL'd out. This will likely cause the call to trace_rxrpc_rx_done() to oops. Fix this by moving the unsharing down to where rxrpc_input_call_event() calls rxrpc_input_call_packet(). There are a number of places prior to that where we ignore DATA packets for a variety of reasons (such as the call already being complete) for which an unshare is then avoided. And with that, rxrpc_input_packet() doesn't need to take a pointer to the pointer to the packet, so change that to just a pointer.

Products: Kernel
Affected versions: Not specified
Fixed versions: 6.12.86, 6.18.27, 6.6.140, 7.0.4
CVEs: CVE-2026-45998
Confirmed fixed CVEs: Not specified
Updated in this feed: 3 Nov 2026, 11:36 UTC · Revision 1

Source evidence

rxrpc: Fix potential UAF after skb_unshare() failure

core-osv · Original source

Published 27 May 2026, 12:55 UTC

osv:CVE-2026-45998

Kernel

Fixed versions: 6.6.140, 6.12.86, 6.18.27, 7.0.4

Complete source record

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  "url": "https://osv.dev/vulnerability/CVE-2026-45998",
  "method": "structured",
  "payload": {
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    "title": "rxrpc: Fix potential UAF after skb_unshare() failure",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix potential UAF after skb_unshare() failure If skb_unshare() fails to unshare a packet due to allocation failure in rxrpc_input_packet(), the skb pointer in the parent (rxrpc_io_thread()) will be NULL'd out. This will likely cause the call to trace_rxrpc_rx_done() to oops. Fix this by moving the unsharing down to where rxrpc_input_call_event() calls rxrpc_input_call_packet(). There are a number of places prior to that where we ignore DATA packets for a variety of reasons (such as the call already being complete) for which an unshare is then avoided. And with that, rxrpc_input_packet() doesn't need to take a pointer to the pointer to the packet, so change that to just a pointer.",
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      "modified": "2026-10-28T02:30:28.431449462Z",
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  "source_id": "core-osv",
  "document_id": 495031,
  "published_at": "2026-05-27T12:55:52.756+00:00"
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