CVE-2026-52933

In the Linux kernel, the following vulnerability has been resolved: io_uring/poll: fix signed comparison in io_poll_get_ownership() io_poll_get_ownership() uses a signed comparison to check whether poll_refs has reached the threshold for the slowpath: if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS)) atomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG (BIT(31)) is set in poll_refs, the value becomes negative in signed arithmetic, so the >= 128 comparison always evaluates to false and the slowpath is never taken. Fix this by casting the atomic_read() result to unsigned int before the comparison, so that the cancel flag is treated as a large positive value and correctly triggers the slowpath.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/326941b22806cbf2df1fbfe902b7908b368cce42	Patch
https://git.kernel.org/stable/c/81bf96b0abbfa4cd47ea32e12596aed3855fb2f3	Patch
https://git.kernel.org/stable/c/c6d191164dc81838d8dbf452a6000f68c558d1ae	Patch
https://git.kernel.org/stable/c/cf522703d4f194991615763697ae25a3f9539763	Patch
https://git.kernel.org/stable/c/ea0697129807d718037f618221037aa0660ee3c5	Patch
https://git.kernel.org/stable/c/fc47043f3d9af3efa407665b47f8378ec691ba18	Patch
https://cert-portal.siemens.com/productcert/html/ssa-019113.html

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.1:-::::::
	cpe:2.3:o:linux:linux_kernel:6.1:rc7::::::
	cpe:2.3:o:linux:linux_kernel:6.1:rc8::::::

History

No history.

Information

Published : 2026-06-24 08:16

Updated : 2026-09-08 09:18

NVD link : CVE-2026-52933

Mitre link : CVE-2026-52933

CVE.ORG link : CVE-2026-52933

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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