CVE-2026-52933
Vulnerability Summary
Timeline
Description
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 Metrics
- v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Trends
Current EPSS score: 0.12%• Percentile: 2%
Techniques & Countermeasures
- CWE-835•Loop with Unreachable Exit Condition ('Infinite Loop')
The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.
Affected Systems
- debian•linux
< 6.1.176-1 | < 6.12.86-1 | < 7.0.4-1
- debian•linux-6.1
< 6.1.176-1~deb11u1
- ubuntu•linux
all | < 6.8.0-136.136 | all | < 7.0.0-27.27
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
all | < 6.8.0-1061.64 | all | < 7.0.0-1008.8
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.15
all
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.14
all
- ubuntu•linux-aws-6.17
all
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-6.8
< 6.8.0-1061.64~22.04.1
- ubuntu•linux-aws-fips
all | < 6.8.0-1061.64+fips1
- ubuntu•linux-azure
all | all | < 6.8.0-1063.71 | all | < 7.0.0-1010.10
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.15
all
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.11
all
- ubuntu•linux-azure-6.14
all
- ubuntu•linux-azure-6.17
all
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-6.8
< 6.8.0-1063.71~22.04.1
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all | all | < 6.8.0-1062.69 | all | < 7.0.0-1009.9
- ubuntu•linux-azure-fde-5.15
all
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.14
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fde-6.8
< 6.8.0-1062.69~22.04.1
- ubuntu•linux-azure-fips
all | < 6.8.0-1063.71+fips2
- ubuntu•linux-azure-nvidia
all
- ubuntu•linux-azure-nvidia-6.14
all
- ubuntu•linux-bluefield
all | < 6.8.0-1028.33
- ubuntu•linux-fips
all | < 6.8.0-136.136+fips2
- ubuntu•linux-gcp
all | all | < 6.8.0-1064.72 | all | < 7.0.0-1007.7
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.15
all
- ubuntu•linux-gcp-5.19
all
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.8
all
Showing first 50 affected entries in server-rendered view.
References (31)
- https://git.kernel.org/stable/c/81bf96b0abbfa4cd47ea32e12596aed3855fb2f3
- https://git.kernel.org/stable/c/cf522703d4f194991615763697ae25a3f9539763
- https://git.kernel.org/stable/c/fc47043f3d9af3efa407665b47f8378ec691ba18
- https://git.kernel.org/stable/c/ea0697129807d718037f618221037aa0660ee3c5
- https://git.kernel.org/stable/c/c6d191164dc81838d8dbf452a6000f68c558d1ae
- https://git.kernel.org/stable/c/326941b22806cbf2df1fbfe902b7908b368cce42
- https://ubuntu.com/security/CVE-2026-52933
- https://www.cve.org/CVERecord?id=CVE-2026-52933
- https://git.kernel.org/linus/326941b22806cbf2df1fbfe902b7908b368cce42
- https://ubuntu.com/security/notices/USN-8488-1
- https://ubuntu.com/security/notices/USN-8489-1
- https://ubuntu.com/security/notices/USN-8488-2
- https://ubuntu.com/security/notices/USN-8507-1
- https://ubuntu.com/security/notices/USN-8569-1
- https://ubuntu.com/security/notices/USN-8567-1
- https://ubuntu.com/security/notices/USN-8574-1
- https://ubuntu.com/security/notices/USN-8574-2
- https://ubuntu.com/security/notices/USN-8595-1
- https://ubuntu.com/security/notices/USN-8596-1
- https://ubuntu.com/security/notices/USN-8603-1
- https://ubuntu.com/security/notices/USN-8595-2
- https://ubuntu.com/security/notices/USN-8606-1
- https://ubuntu.com/security/notices/USN-8607-1
- https://ubuntu.com/security/notices/USN-8608-1
- https://ubuntu.com/security/notices/USN-8609-1
- https://ubuntu.com/security/notices/USN-8574-3
- https://ubuntu.com/security/notices/USN-8595-3
- https://ubuntu.com/security/notices/USN-8619-1
- https://security-tracker.debian.org/tracker/CVE-2026-52933
- https://ubuntu.com/security/notices/USN-8665-1
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html