CVE-2026-53274 | net/smc: fix sleep-inside-lock in __smc_setsockopt() causing local DoS

In the Linux kernel, the following vulnerability has been resolved: net/smc: fix sleep-inside-lock in __smc_setsockopt() causing local DoS A logic flaw in __smc_setsockopt() allows a local unprivileged user to cause a Denial of Service (DoS) by holding the socket lock indefinitely. The function __smc_setsockopt() calls copy_from_sockptr() while holding lock_sock(sk). By passing a userfaultfd-monitored memory page (or FUSE-backed memory on systems where unprivileged userfaultfd is disabled) as the optval, an attacker can halt execution during the copy operation, keeping the lock held. Combined with asynchronous tear-down operations like shutdown(), this exhausts the kernel wq (kworkers) and triggers the hung task watchdog. [ 240.123456] INFO: task kworker/u8:2 blocked for more than 120 seconds. [ 240.123489] Call Trace: [ 240.123501] smc_shutdown+... [ 240.123512] lock_sock_nested+... This patch moves the user-space copy outside the lock_sock() critical section to prevent the issue.

Published: 2026-06-25 Last update: 2026-06-30 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2026-53274 is rated Low Risk (7.8/100): low exploitation likelihood (EPSS 0.18%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-53274

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-25 0.18%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-53274

CVSS metrics for this CVE.

No CVSS data in dataset for this CVE.

Weakness enumeration for CVE-2026-53274

GitHub Security Advisory for CVE-2026-53274

GHSA-22m3-g27g-5h2v · Severity: unknown — In the Linux kernel, the following vulnerability has been resolved: net/smc: fix sleep-inside...

OS Trackers for CVE-2026-53274

vendor priority summary link
debian unimportant CVE-2026-53274 unimportant priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6. https://security-tracker.debian.org/tracker/CVE-2026-53274
redhat low https://access.redhat.com/security/cve/CVE-2026-53274
suse medium CVE-2026-53274 severity moderate: SUSE including 18 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 87 product×package rows across 19 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise Live Patching 12 SP5, … (19 product lines)): Known Not Affected 87. https://www.suse.com/security/cve/CVE-2026-53274/
ubuntu medium CVE-2026-53274 medium priority: Ubuntu including 162 source packages (linux, linux-allwinner-5.19, …), 1458 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1051, ignored 172, released 88, not-affected 79, needed 68. https://ubuntu.com/security/CVE-2026-53274

Affected software / configurations for CVE-2026-53274

Vendor Product Version Raw CPE
linux linux_kernel >= 5.18, < 6.1.176 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 6.6.143 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 6.12.94 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 6.18.36 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 7.0.13 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 7.1 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2026-53274

cvelogic Threat Intelligence