CVE-2026-31638

Full vulnerability record from the local CVENow database.
Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Only put the call ref if one was acquired rxrpc_input_packet_on_conn() can process a to-client packet after the current client call on the channel has already been torn down. In that case chan->call is NULL, rxrpc_try_get_call() returns NULL and there is no reference to drop. The client-side implicit-end error path does not account for that and unconditionally calls rxrpc_put_call(). This turns a protocol error path into a kernel crash instead of rejecting the packet. Only drop the call reference if one was actually acquired. Keep the existing protocol error handling unchanged.
Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-24 15:16:43.127000
Last modified
2026-10-19 19:18:02.613000
View original CVE JSON
{
  "id": "CVE-2026-31638",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-04-24T15:16:43.127",
  "lastModified": "2026-10-19T19:18:02.613",
  "vulnStatus": "Modified",
  "cveTags": [],
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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: Only put the call ref if one was acquired\n\nrxrpc_input_packet_on_conn() can process a to-client packet after the\ncurrent client call on the channel has already been torn down.  In that\ncase chan->call is NULL, rxrpc_try_get_call() returns NULL and there is\nno reference to drop.\n\nThe client-side implicit-end error path does not account for that and\nunconditionally calls rxrpc_put_call().  This turns a protocol error\npath into a kernel crash instead of rejecting the packet.\n\nOnly drop the call reference if one was actually acquired.  Keep the\nexisting protocol error handling unchanged."
    }
  ],
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              "versionType": "original_commit_for_fix",
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          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
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