Answer in brief
CVE-2026-98258 records a Unknown severity vulnerability in posix-cpu-timers: Prevent freeing a timer which is queued on the expiry list. 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 | >=bf635681c906ad056d1fda325de8d1c12c9f8201 <9971dac1a77845ff467146915fcbb9170f6a8209 || >=bf635681c906ad056d1fda325de8d1c12c9f8201 <4336e3f47d9d516441066e9a65eaf076790d8d45 || >=bf635681c906ad056d1fda325de8d1c12c9f8201 <c21eaa72f02fc6e85621cbe09d303d8fb8bd39cd | 9971dac1a77845ff467146915fcbb9170f6a8209, 4336e3f47d9d516441066e9a65eaf076790d8d45, c21eaa72f02fc6e85621cbe09d303d8fb8bd39cd |
| Linux/Linuxgeneric | 6.13 | Not reported |
Published upstream
Oct 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 6, 2026
In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: Prevent freeing a timer which is queued on the expiry list Kijo analyzed another race in the POSIX CPU timer code: Commit bf635681c906 converted cpu_timer::firing from a tristate value to a boolean. This lost the distinction between "not owned by the firing list" and "still owned, but delivery was canceled". The resulting race is: expiry handler timer_settime() timer_delete() -------------- --------------- -------------- collect timer onto private firing list firing = true observes firing = true firing = false return TIMER_RETRY wait for handler observes firing = false finish deletion unhash and free timer resume list traversal read freed elist.next -> UAF The firing bit is clearly the wrong indicator since that commit. Check whether the timer is queued on the expiry list or not instead. If it is queued clear the firing bit to prevent signal delivery as before and return TIMER_RETRY so the caller unlocks the timer which allows the expiry code to make progress and remove it from the list.
Quoted source text, attributed separately from HOL analysis.