CVE-2026-74436

In the Linux kernel, the following vulnerability has been resolved: rxrpc: serialize kernel accept preallocation with socket teardown rxrpc_kernel_charge_accept() reads rx->backlog without any socket/backlog synchronization and passes that raw pointer into rxrpc_service_prealloc_one(). A concurrent rxrpc_discard_prealloc() sets rx->backlog = NULL and frees the backlog rings, so a kernel preallocation worker can keep using a freed struct rxrpc_backlog while updating *_backlog_head/tail and array slots. Serialize the state check and backlog lookup with the socket lock, and reject kernel preallocation once teardown has disabled listening or discarded the service backlog.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0337cdba0c477f176c0459bed012109453184573
https://git.kernel.org/stable/c/11b429b84c87cb5a0152f14e7d6cb649ed363901
https://git.kernel.org/stable/c/1741378a7a83dfd8e53a9196730df709b903cd33
https://git.kernel.org/stable/c/35a967ff8b24db09ee429c39c5b5e6571639997d
https://git.kernel.org/stable/c/c20d983968f239574290cf804a58cde18ad1c559
https://git.kernel.org/stable/c/d6207326b4ca0ae1041281b6af9df53f8080669a
https://git.kernel.org/stable/c/dc175389b18c29a5303ee83169ec653adfae3e17
https://git.kernel.org/stable/c/dfa0b2bbc5e50119f89c6b5407faa5ed86dfa7c5

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 06:22

Updated : 2026-08-23 13:16

NVD link : CVE-2026-74436

Mitre link : CVE-2026-74436

CVE.ORG link : CVE-2026-74436

JSON object : View

Products Affected

No product.

CWE

No CWE.

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A concurrent rxrpc_discard_prealloc()\nsets rx->backlog = NULL and frees the backlog rings, so a kernel\npreallocation worker can keep using a freed struct rxrpc_backlog\nwhile updating *_backlog_head/tail and array slots.\n\nSerialize the state check and backlog lookup with the socket lock,\nand reject kernel preallocation once teardown has disabled\nlistening or discarded the service backlog."}], "lastModified": "2026-08-23T13:16:43.573", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}