Kernel crash via uninitialized COMEDI detach state
Published May 1, 2026 · Updated May 1, 2026
NULL pointer dereference in the Linux Kernel ni_atmio16d driver allows local users to crash the system after a failed COMEDI attach. The atmio16d_detach() cleanup path calls reset_atmio16d() unconditionally even when atmio16d_attach() failed before dev->private and dev->iobase were initialized. Reachability requires local access and a failed attachment at that stage; the null dereference crashes the kernel, while an unset I/O base can cause unintended low-port writes.
Summary
What happened
NULL pointer dereference in the Linux Kernel ni_atmio16d driver allows local users to crash the system after a failed COMEDI attach. The atmio16d_detach() cleanup path calls reset_atmio16d() unconditionally even when atmio16d_attach() failed before dev->private and dev->iobase were initialized. Reachability requires local access and a failed attachment at that stage; the null dereference crashes the kernel, while an unset I/O base can cause unintended low-port writes.
The record
- CVE
- CVE-2026-31749
- Published
- May 1, 2026
- Updated
- May 1, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-476, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 1, 2026CVE publishedPublication date reported by the CVE source.
- May 1, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <101ab946b79ad83b36d5cfd47de587492a80acf0
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <3848ae00b1642e2c98ff8cbfd2d3b38c6f53b5c3
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <43c68a2c7cc35b7c2a83c285cb4ad3d472b8caa2
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <5d8d88c8c0eec230de8f1f60e0920a4337939a88
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <933a2d6a95f9bfb203e562c9be1dd990c735535c
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <a01dd339ea6ac58b0967a50085622a6017351140
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <d07d97ca4f7fac467cdcf4a012690853958b7e89
- Affected versionversion=2323b276308a5da5774b778f39c7fd94b2a3022a <f517646e008fe99ca1800601cd011b110f8684ae
- Affected versionversion=2.6.30
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo