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TI-2026-84225 Aliases CVE-2026-99263GHSA-jcvr-9jrw-gr2r

Lost wakeup in io_uring poll retry path in Linux kernel

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Fixed

No CVSS vector from any source. Fix status from CNA.

Summary

The io_uring poll code in the Linux kernel can lose a retry wakeup when the owning task drops ownership of a request. The request then stalls until an unrelated wakeup arrives. Affected are Linux kernel versions from 5.15.82 before 5.16, from 6.0.11 before 6.1, and from 6.1.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: io_uring/poll: avoid retry wakeup loss when dropping ownership If a wakeup sets IO_POLL_RETRY_FLAG between the owning task consuming the existing instance of IO_POLL_RETRY_FLAG and the loop check of io_poll_check_events(), then we stall on processing the request until an unrelated wakeup comes along. Using atomic_cmpxchg instead of atomic_sub_return to guarantee both the count v and poll_refs are 0 and no wake-ups are missed.

Why it matters now

EPSS 0.00197 9th percentileScored 2026-11-04
Fix Fixed Linux (Linux): 5.16, 6.1, 6.1.191 +6

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15.82 to before 5.16; 6.0.11 to before 6.15.16, 6.1Patch availableCNA
LinuxLinux6.1 and later6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1, 7.4-rc1Patch availableCNA
  • Linux VendorLinux Affected 5.15.82 to before 5.16; 6.0.11 to before 6.1 Fixed in 5.16, 6.1 Patch available CNA
  • Linux VendorLinux Affected 6.1 and later Fixed in 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1, 7.4-rc1 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Upgrade the Linux kernel to 5.16, 6.1, 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1 or 7.4-rc1, depending on the release branch in use.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 5.16, 6.1
  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1, 7.4-rc1

Timeline

  1. 2026-11-03 Threatist record created from CVE-2026-99263
  2. 2026-11-03 Alias added: GHSA-jcvr-9jrw-gr2r
  3. 2026-11-03 Fix available: Linux/[email protected], Linux/Linux@937d38dcacd675dc0572d6c9b6743960df3128ed · CNA
  4. 2026-11-03 1 new reference · CNA

References

Other 7

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences