CVE-2026-91007zephyrproject zephyr untrusted pointer dereference
CVE-2026-91007 is a untrusted pointer dereference in zephyrproject zephyr, rated high (7.8 on CVSS 3.1).
Why this priority: High severity, with no exploitation signal yet.
Published · Updated · NVD status: Awaiting Analysis
What it is
A pointer value from outside is used directly.
How it is reached
An attacker can exploit it by someone who can already run code or sign in on the machine, with an ordinary user account, and nobody has to click anything.
What an attacker gains
A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker crash the process, read memory, or in the worst case run code.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- Upgrade zephyrproject zephyr to a fixed version for your release line (4.3.2, 4.5.0).
- Limit who can run code or sign in on the hosts that run it.
Description from NVD
The user-mode syscall verifiers for the charger driver API in drivers/charger/charger_handlers.c did not inspect the prop argument before copying union charger_propval across the user/kernel boundary. Two members of that union are function pointers — status_notification (CHARGER_PROP_STATUS_NOTIFICATION) and online_notification (CHARGER_PROP_ONLINE_NOTIFICATION), declared in include/zephyr/drivers/charger.h — and z_vrfy_charger_set_prop() forwarded the caller-supplied union verbatim to the driver's set_property callback for any property. z_vrfy_charger_get_prop() had the mirror defect and copied the stored kernel callback address back out to user memory.
With CONFIG_USERSPACE enabled, any user-mode thread that has been granted a charger device object could call charger_set_prop() with CHARGER_PROP_STATUS_NOTIFICATION or CHARGER_PROP_ONLINE_NOTIFICATION and an arbitrary pointer value. Drivers that implement these properties — drivers/charger/charger_max20335.c, drivers/charger/charger_pf1550.c and drivers/charger/charger_bq2518x.c — store the pointer in device data and later invoke it from their interrupt work handlers, which run in supervisor mode, on any charger state change such as a cable plug/unplug.
The result is a control-flow hijack at kernel privilege from an unprivileged thread, defeating the isolation that CONFIG_USERSPACE is meant to provide; the read path additionally disclosed a kernel code address to user mode, and clearing a notifier installed by a supervisor thread let user mode suppress charger notifications. Supervisor-mode callers of charger_set_prop()/charger_get_prop() are unaffected.
The fix makes both verifiers reject the two notifier properties outright — including when the supplied callback is NULL, since the notifiers are device state — and adds a BUILD_ASSERT on CHARGER_PROP_COMMON_COUNT so that new properties force a re-review of the union's user-mode safety.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Native code: operating systems, browsers and firmware. The flaw sits wherever native code reads untrusted data.
- Network appliances and media or file parsers. The flaw sits wherever native code reads untrusted data.
Trust boundaries in play
- Host boundary. The attacker needs a foothold on the machine first; the flaw turns a small foothold into a bigger one.
- Wherever native code reads untrusted data. An attacker who crosses it can crash the process, read memory, or in the worst case run code.
Questions to answer about your own systems
- Where does zephyrproject zephyr run in your systems, and at which version?
- Which of those hosts also run code or users you do not fully trust?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.