Answer in brief
CVE-2026-99243 records a Unknown severity vulnerability in io-wq: order the exit bit against worker creation task work. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=4b4e5bbf9386d4ec21d91c0cb0fd60b9bba778ec <67da3eec264aeb67835886720243ae2dc1463315 || >=71a85387546e50b1a37b0fa45dadcae3bfb35cf6 <a63c752157eacf49f628359822666b32503d194a || >=71a85387546e50b1a37b0fa45dadcae3bfb35cf6 <1432d881d99584105122760133caeff1dce7a9f7 || >=71a85387546e50b1a37b0fa45dadcae3bfb35cf6 <6cf012a4d5e461c788ecc9dbed67adc31a142644 || >=71a85387546e50b1a37b0fa45dadcae3bfb35cf6 <0d81cdd433b0a96c5275c01b8172e0b1f71dd595 || >=71a85387546e50b1a37b0fa45dadcae3bfb35cf6 <75395db7a9b40a2e826c838e648fef8ed1a2d174 || >=71a85387546e50b1a37b0fa45dadcae3bfb35cf6 <31fc780b75b278d37700373d54a99fdb4117fdd6 || >=5.15.11 <5.15.224 | 67da3eec264aeb67835886720243ae2dc1463315, a63c752157eacf49f628359822666b32503d194a, 1432d881d99584105122760133caeff1dce7a9f7, 6cf012a4d5e461c788ecc9dbed67adc31a142644, 0d81cdd433b0a96c5275c01b8172e0b1f71dd595, 75395db7a9b40a2e826c838e648fef8ed1a2d174, 31fc780b75b278d37700373d54a99fdb4117fdd6, 5.15.224 |
| Linux/Linuxgeneric | 5.16 | Not reported |
Published upstream
Nov 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 3, 2026
In the Linux kernel, the following vulnerability has been resolved: io-wq: order the exit bit against worker creation task work io_wq_exit_workers() cancels task work for queued worker creation with task_work_cancel_match(). That has a plain load of task->task_works. io_queue_worker_create() adds the new entry and tests IO_WQ_BIT_EXIT to cancel it if the workqueue is already on its way out. That must be ordered. task_work_add() has a full barrier via cmpxchg(). But io_wq_exit_start() sets the bit with set_bit() which doesn't have any memory ordering. So afaict, on weakly ordered architectures the exiting task may load task_works before the store of the bit is visible. The other side tests the bit before the store is visible as well. So the entry remains queued with worker_refs and the exiting task waits on worker_done indefinitely. If the task still has rings then io_uring_del_tctx_node() provides the barrier via test_and_set_bit() in io_wq_set_exit_on_idle(). When it has closed all rings though that barrier is gone. Add the barrier after the set_bit().
Quoted source text, attributed separately from HOL analysis.