CVE-2025-68335 — comedi: pcl818: fix null-ptr-deref in pcl818_ai_cancel()
In the Linux kernel, the following vulnerability has been resolved: comedi: pcl818: fix null-ptr-deref in pcl818_ai_cancel() Syzbot identified an issue [1] in pcl818_ai_cancel(), which stems from the fact that in case of early device detach via pcl818_detach(), subdevice dev->read_subdev may not have initialized its pointer to &struct comedi_async as intended. Thus, any such dereferencing of &s->async->cmd will lead to general protection fault and kernel crash. Mitigate this problem by removing a call to pcl818_ai_cancel() from pcl818_detach() altogether. This way, if the subdevice setups its support for async commands, everything async-related will be handled via subdevice's own ->cancel() function in comedi_device_detach_locked() even before pcl818_detach(). If no support for asynchronous commands is provided, there is no need to cancel anything either. [1] Syzbot crash: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 1 UID: 0 PID: 6050 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:pcl818_ai_cancel+0x69/0x3f0 drivers/comedi/drivers/pcl818.c:762 ... Call Trace: <TASK> pcl818_detach+0x66/0xd0 drivers/comedi/drivers/pcl818.c:1115 comedi_device_detach_locked+0x178/0x750 drivers/comedi/drivers.c:207 do_devconfig_ioctl drivers/comedi/comedi_fops.c:848 [inline] comedi_unlocked_ioctl+0xcde/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] ...
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < b2a5b172dc05be6c4f2c5542c1bbc6b14d60ff16≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < 935ad4b3c325c24fff2c702da403283025ffc722≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < 88d99ca5adbd01ff088f5fb2ddeba5755e085e52≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < 5caa40e7c6a43e08e3574f990865127705c22861≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < d948c53dec36dafe182631457597c49c1f1df5ea≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < 877adccfacb32687b90714a27cfb09f444fdfa16≥ 00aba6e7b5653a6607238ecdab7172318059d984 and < a51f025b5038abd3d22eed2ede4cd46793d89565version 3.15 | Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.19%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Deferred
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
7 on the record
- git.kernel.org/stable/c/a51f025b5038abd3d22eed2ede4cd46793d89565
- git.kernel.org/stable/c/d948c53dec36dafe182631457597c49c1f1df5ea
- git.kernel.org/stable/c/877adccfacb32687b90714a27cfb09f444fdfa16
- git.kernel.org/stable/c/935ad4b3c325c24fff2c702da403283025ffc722
- git.kernel.org/stable/c/b2a5b172dc05be6c4f2c5542c1bbc6b14d60ff16
- git.kernel.org/stable/c/88d99ca5adbd01ff088f5fb2ddeba5755e085e52
- git.kernel.org/stable/c/5caa40e7c6a43e08e3574f990865127705c22861
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 8h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 8h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-68335 is "comedi: pcl818: fix null-ptr-deref in pcl818_ai_cancel()", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.19% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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