CVE-2026-23311: Linux kernel · perf/core: Fix invalid wait context in ctx_sched_in()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.09% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: perf/core: Fix invalid wait context in ctx_sched_in() Lockdep found a bug in the event scheduling when a pinned event was failed and wakes up the threads in the ring buffer like below. It seems it should not grab a wait-queue lock under perf-context lock. Let's do it with irq_work. [ 39.913691] ============================= [ 39.914157] [ BUG: Invalid wait context ] [ 39.914623] 6.15.0-next-20250530-next-2025053 #1 Not tainted [ 39.915271] ----------------------------- [ 39.915731] repro/837 is trying to lock: [ 39.916191] ffff88801acfabd8 (&event->waitq){....}-{3:3}, at: __wake_up+0x26/0x60 [ 39.917182] other info that might help us debug this: [ 39.917761] context-{5:5} [ 39.918079] 4 locks held by repro/837: [ 39.918530] #0: ffffffff8725cd00 (rcu_read_lock){....}-{1:3}, at: __perf_event_task_sched_in+0xd1/0xbc0 [ 39.919612] #1: ffff88806ca3c6f8 (&cpuctx_lock){....}-{2:2}, at: __perf_event_task_sched_in+0x1a7/0xbc0 [ 39.920748] #2: ffff88800d91fc18 (&ctx->lock){....}-{2:2}, at: __perf_event_task_sched_in+0x1f9/0xbc0 [ 39.921819] #3: ffffffff8725cd00 (rcu_read_lock){....}-{1:3}, at: perf_event_wakeup+0x6c/0x470
References
- ubuntu.com/security/CVE-2026-23311 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23311 (opens in a new tab)
- git.kernel.org/linus/486ff5ad49bc50315bcaf6d45f04a33ef0a45ced (opens in a new tab)
- git.kernel.org/stable/c/486ff5ad49bc50315bcaf6d45f04a33ef0a45ced (opens in a new tab)
- git.kernel.org/stable/c/825f218ca70ef394c2b8546b313711d867b24584 (opens in a new tab)
- git.kernel.org/stable/c/c67ab059953e3b66cb17ddd6524c23f9e1f6526d (opens in a new tab)