{"id":"CVE-2026-52933","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/poll: fix signed comparison in io_poll_get_ownership()\n\nio_poll_get_ownership() uses a signed comparison to check whether\npoll_refs has reached the threshold f…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/poll: fix signed comparison in io_poll_get_ownership()\n\nio_poll_get_ownership() uses a signed comparison to check whether\npoll_refs has reached the threshold f…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-835","CWE-1024"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.15.82, < 5.16","linux_kernel >= 6.0.11, < 6.1","linux_kernel >= 6.1.1, < 6.1.175","linux_kernel >= 6.2, < 6.6.140","linux_kernel >= 6.7, < 6.12.86","linux_kernel >= 6.13, < 6.18.27","linux_kernel >= 6.19, < 7.0.4","linux_kernel = 6.1"],"patched":["linux_kernel 7.0.4"],"published":"2026-06-24","updated":"2026-09-08","sourceUpdated":"2026-09-08T09:18:11.540","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-52933","references":[{"url":"https://git.kernel.org/stable/c/326941b22806cbf2df1fbfe902b7908b368cce42","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/81bf96b0abbfa4cd47ea32e12596aed3855fb2f3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c6d191164dc81838d8dbf452a6000f68c558d1ae","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cf522703d4f194991615763697ae25a3f9539763","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ea0697129807d718037f618221037aa0660ee3c5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fc47043f3d9af3efa407665b47f8378ec691ba18","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52933.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-52933"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2492097"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-52933"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52933"},{"url":"https://lore.kernel.org/linux-cve-announce/2026062433-CVE-2026-52933-815c@gregkh/T"},{"url":"https://access.redhat.com/errata/RHSA-2026:64808"},{"url":"https://access.redhat.com/errata/RHSA-2026:64775"},{"url":"https://access.redhat.com/errata/RHSA-2026:65708"},{"url":"https://access.redhat.com/errata/RHSA-2026:67114"},{"url":"https://access.redhat.com/errata/RHSA-2026:68100"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.0012,"epssPercentile":0.02123,"ingestedAt":"2026-09-08T13:33:25.116Z","slug":"CVE-2026-52933","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/poll: fix signed comparison in io_poll_get_ownership()\n\nio_poll_get_ownership() uses a signed comparison to check whether\npoll_refs has reached the threshold for the slowpath:\n\n    if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS))\n\natomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG\n(BIT(31)) is set in poll_refs, the value becomes negative in\nsigned arithmetic, so the >= 128 comparison always evaluates to\nfalse and the slowpath is never taken.\n\nFix this by casting the atomic_read() result to unsigned int\nbefore the comparison, so that the cancel flag is treated as a\nlarge positive value and correctly triggers the slowpath.\n\n## Affected\n\n- `linux_kernel >= 5.15.82, < 5.16`\n- `linux_kernel >= 6.0.11, < 6.1`\n- `linux_kernel >= 6.1.1, < 6.1.175`\n- `linux_kernel >= 6.2, < 6.6.140`\n- `linux_kernel >= 6.7, < 6.12.86`\n- `linux_kernel >= 6.13, < 6.18.27`\n- `linux_kernel >= 6.19, < 7.0.4`\n- `linux_kernel = 6.1`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.0.4`\n\n## Vendor advisories\n\n- **RHSA-2026:64808** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:64808)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 9 · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52933.json)\n- **RHSA-2026:64775** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), Red Hat Enterprise Linux Real Time (v. 10) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:64775)\n- **RHSA-2026:65708** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6), Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6), Red Hat Enterprise Linux Real Time EUS (v.9.6) · released 2026-09-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:65708)\n- **RHSA-2026:67114** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0), Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0), Red Hat Enterprise Linux Real Time EUS (v. 10.0) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67114)\n- **RHSA-2026:68100** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4), Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4), Red Hat Enterprise Linux Real Time E4S (v.9.4) · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68100)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}