Answer in brief
CVE-2026-89747 records a Unknown severity vulnerability in tracing: Fix use-after-free in trace_pipe read on sub-buffer order change. 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 | >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <05ebe1e1d7d38c2612bacfefe043a33572ae34cb || >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <ddbe921ed16a0ad2d9e09574c3f3aabec7528325 || >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <7a49d19ff9baaf61217e5ec14199c18bc2d93ee4 || >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <372f8534244d632ad5118e8a87a11291b01712d3 | 05ebe1e1d7d38c2612bacfefe043a33572ae34cb, ddbe921ed16a0ad2d9e09574c3f3aabec7528325, 7a49d19ff9baaf61217e5ec14199c18bc2d93ee4, 372f8534244d632ad5118e8a87a11291b01712d3 |
| Linux/Linuxgeneric | 6.8 | Not reported |
Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 11, 2026
In the Linux kernel, the following vulnerability has been resolved: tracing: Fix use-after-free in trace_pipe read on sub-buffer order change Writing to buffer_subbuf_size_kb calls ring_buffer_subbuf_order_set(), which frees every sub-buffer of the ring buffer, including the reader page, and replaces them with newly allocated ones. Readers of trace_pipe hold pointers into those pages. ring_buffer_peek() looks up an event under cpu_buffer->reader_lock but returns the event pointer after dropping the lock, and peek_next_entry() then calls ring_buffer_event_length() and ring_buffer_event_data() on it. If the sub-buffer order is changed in that window, the reader dereferences freed memory: BUG: KASAN: use-after-free in ring_buffer_peek+0x3e0/0x430 Read of size 1 at addr ffff88802a4cf010 by task syz-executor989/6002 Freed by: free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 Take trace_access_lock(RING_BUFFER_ALL_CPUS) around the order change. This is the lock trace_pipe readers already hold across their entire peek-and-print loop, so the swap can no longer race with a reader that is dereferencing a peeked event.
Quoted source text, attributed separately from HOL analysis.