CVE-2026-90325blk-cgroup: skip dying blkg in blkcg_activate_policy()
Updated under an hour ago ()
Does this affect you?
It affects Linux. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: skip dying blkg in blkcg_activate_policy() When switching IO schedulers on a block device, blkcg_activate_policy() can race with concurrent blkcg deletion, leading to a use-after-free in rcu_accelerate_cbs. T1: T2: blkg_destroy kill(&blkg->refcnt) // blkg->refcnt=1->0 blkg_release // call_rcu(__blkg_release) ... blkg_free_workfn ->pd_free_fn(pd) elv_iosched_store elevator_switch ... iterate blkg list blkg_get(blkg) // blkg->refcnt=0->1 list_del_init(&blkg->q_node) blkg_put(pinned_blkg) // blkg->refcnt=1->0 blkg_release // call_rcu again rcu_accelerate_cbs // uaf Fix this by checking hlist_unhashed(&blkg->blkcg_node) before getting a reference to the blkg. This is the same check used in blkg_destroy() to detect if a blkg has already been destroyed. If the blkg is already unhashed, skip processing it since it's being destroyed.
- CVSS
- 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Received
- Record last updated
- Oct 19, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from 81c1188905f88b77743d1fdeeedfc8cb7b67787d before b5dae1cd0d8368b4338430ff93403df67f0b8bcc; from bfe46d2efe46c5c952f982e2ca94fe2ec5e58e2a before 083b58373463a6e5ee60ecb135269348f68ad7df; from f1c006f1c6850c14040f8337753a63119bba39b9 before 1a267295b1ea6a6477963f3fda84adfecd48fcad; from f1c006f1c6850c14040f8337753a63119bba39b9 before 7337d012ca3fc3a6a2d1c8e2a19c6d97c38b410d; from f1c006f1c6850c14040f8337753a63119bba39b9 before 3d8c3da95c75a4d312e272fc7b4076dd3ba9115c; from f1c006f1c6850c14040f8337753a63119bba39b9 before d8c872901e6459339374e9eea80aa919176c2ccd; from f1c006f1c6850c14040f8337753a63119bba39b9 before 5e9220389920f33b6a804d50c548cd0cd1b04634; from 6.1.16 before 6.1.17; and 1 more ranges | CNA record |
References
- https://git.kernel.org/stable/c/b5dae1cd0d8368b4338430ff93403df67f0b8bcc
- https://git.kernel.org/stable/c/083b58373463a6e5ee60ecb135269348f68ad7df
- https://git.kernel.org/stable/c/1a267295b1ea6a6477963f3fda84adfecd48fcad
- https://git.kernel.org/stable/c/7337d012ca3fc3a6a2d1c8e2a19c6d97c38b410d
- https://git.kernel.org/stable/c/3d8c3da95c75a4d312e272fc7b4076dd3ba9115c
- https://git.kernel.org/stable/c/d8c872901e6459339374e9eea80aa919176c2ccd
- https://git.kernel.org/stable/c/5e9220389920f33b6a804d50c548cd0cd1b04634
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.