CVE-2026-68281: Linux kernel · drm/imagination: Count paired job fence as dependency in prepare_job()
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 6.8.0-147.147 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-147.147, 6.8.0-1067.70, 6.8.0-1071.79 +25
Exploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther 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: drm/imagination: Count paired job fence as dependency in prepare_job() The DRM scheduler's prepare_job() callback counts the remaining non-signaled native dependencies for a job, preventing job submission until those (plus job data and fence update) can fit in the job queue's CCCB. This means checking which dependencies can be waited upon in the firmware, i.e. whether they are backed by a UFO object, i.e. whether their drm_sched_fence::parent has been assigned to a pvr_queue_fence::base fence. That happens when the job owning the fence is submitted to the firmware. Paired geometry and fragment jobs are submitted at the same time, which means the dependency between them can't be checked this way before submission. Update job_count_remaining_native_deps() to take into account the dependency between paired jobs. This fixes cases where prepare_job() underestimated the space left in an almost full fragment CCCB, wrongly unblocking run_job(), which then returned early without writing the full sequence of commands to the CCCB. The above lead to kernel warnings such as the following and potentially job timeouts (depending on waiters on the missing commands): [ 375.702979] WARNING: drivers/gpu/drm/imagination/pvr_cccb.c:178 at pvr_cccb_write_command_with_header+0x2c4/0x330 [powervr], CPU#1: kworker/u16:3/47 [ 375.703160] Modules linked in: [ 375.703571] CPU: 1 UID: 0 PID: 47 Comm: kworker/u16:3 Tainted: G W 7.0.0-rc2-g817eb6b11ad5 #40 PREEMPT [ 375.703613] Tainted: [W]=WARN [ 375.703627] Hardware name: Texas Instruments AM625 SK (DT) [ 375.703645] Workqueue: powervr-sched drm_sched_run_job_work [gpu_sched] [ 375.703741] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 375.703764] pc : pvr_cccb_write_command_with_header+0x2c4/0x330 [powervr] [ 375.703847] lr : pvr_queue_submit_job_to_cccb+0x578/0xa70 [powervr] [ 375.703921] sp : ffff800084a97650 [ 375.703934] x29: ffff800084a97740 x28: 0000000000000958 x27: ffff80008565d000 [ 375.703979] x26: 0000000000000030 x25: ffff800084a97680 x24: 0000000000001000 [ 375.704017] x23: ffff800084a97820 x22: 1ffff00010952ecc x21: 0000000000000008 [ 375.704056] x20: 00000000000006a8 x19: ffff00002ff7da88 x18: 0000000000000000 [ 375.704093] x17: 0000000020020000 x16: 0000000000020000 x15: 0000000000000000 [ 375.704132] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ 375.704168] x11: 000000000000f2f2 x10: 00000000f3000000 x9 : 00000000f3f3f3f3 [ 375.704206] x8 : 00000000f2f2f200 x7 : ffff700010952ecc x6 : 0000000000000008 [ 375.704243] x5 : 0000000000000000 x4 : 1ffff00010acba00 x3 : 0000000000000000 [ 375.704279] x2 : 0000000000000007 x1 : 0000000000000fff x0 : 000000000000002f [ 375.704317] Call trace: [ 375.704331] pvr_cccb_write_command_with_header+0x2c4/0x330 [powervr] (P) [ 375.704411] pvr_queue_submit_job_to_cccb+0x578/0xa70 [powervr] [ 375.704487] pvr_queue_run_job+0x3a4/0x990 [powervr] [ 375.704562] drm_sched_run_job_work+0x580/0xd48 [gpu_sched] [ 375.704623] process_one_work+0x520/0x1288 [ 375.704658] worker_thread+0x3f0/0xb3c [ 375.704680] kthread+0x334/0x3d8 [ 375.704706] ret_from_fork+0x10/0x20 [ 375.704736] ---[ end trace 0000000000000000 ]---
References
- ubuntu.com/security/CVE-2026-68281 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-68281 (opens in a new tab)
- git.kernel.org/stable/c/a673171502e87acb5a9e2923f4cf9dce521fd05e (opens in a new tab)
- git.kernel.org/stable/c/9cd74f935306cd857f46686975c43383e1d95f94 (opens in a new tab)
- git.kernel.org/stable/c/943fa73ea0efa335d9c1800fcfac47915de4ff89 (opens in a new tab)
- git.kernel.org/stable/c/02b0da249c8f78d2bbf9f498bbd371c66142b0af (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8917-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8918-1 (opens in a new tab)