CVE-2026-74631

net: smc: fix splice entry lifetime imbalance in smc_rx_splice

HIGH
8.4
CVSS Score
Published: August 22, 2026 at 03:32 PM UTC
Updated: October 16, 2026 at 08:17 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH8.4
Exploit prediction
EPSS 0.1%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: net: smc: fix splice entry lifetime imbalance in smc_rx_splice smc_rx_splice() passes pages to splice_to_pipe() before taking the references that cover the lifetime of each splice entry. In the VM-backed RMB path, splice_to_pipe() may drop unqueued entries through smc_rx_spd_release(), while queued entries are released later via the pipe buffer callback. The old post-splice accounting also derives the number of queued VM pages from an offset mutated while building the descriptor, and a multi-page splice pairs one sock_hold() with multiple sock_put() calls. Take the page and socket references for every candidate entry before splice_to_pipe(), and drop the matching private state, page reference, and socket reference from smc_rx_spd_release() for entries that never get queued. This fixes a refcount imbalance that can underflow page refcounts and trigger a use-after-free.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.189014db202cb764b8e14c53e7bacc81f9a1a2ba7f
Vendor states this is fixed in 07ad246529d136d5ef441d5ab4c305d132ff3090 (fixed)
Vendor states this is fixed in 0b7d54cedea5cb158e21925ae0c6c2f5c87ed2a0 (fixed)
Vendor states this is fixed in 4515c78f4d9fd577270f012efeb062ea58b3682d (fixed)
Vendor states this is fixed in 5d9686af2976741bbd79b150d1c9e60b81e7f12e (fixed)
Vendor states this is fixed in 7ddc7af2ae7fc5a0c0635b245c0824c8b76de5cb (fixed)
Vendor states this is fixed in af02c67ce654356c58db20a0bb2db33ace3b07a8 (fixed)
Vendor states this is fixed in c841789e456ec6751342fa800639ce8e82ff0e6b (fixed)
Vendor states this is fixed in ca8342b5fc24c249fdb998468f6a168b457c67e5 (fixed)
Vendor states this is fixed in 4.18 (unaffected)
Vendor states this is fixed in 5.10.266 (unaffected)
Vendor states this is fixed in 5.15.217 (unaffected)
Vendor states this is fixed in 6.1.183 (unaffected)
Vendor states this is fixed in 6.12.104 (unaffected)
Vendor states this is fixed in 6.18.45 (unaffected)
Vendor states this is fixed in 6.6.152 (unaffected)
Vendor states this is fixed in 7.1.9 (unaffected)
Vendor states this is fixed in 7.2 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.4HIGHLinux
Vector?

Quick Info

StatusRECEIVED

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