CVSS 3.1
7.8 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVE-2026-91007 Arbitrary supervisor-mode function pointer injection via charger_set_prop() syscall in the charger driver API
High (7.8) in zephyrproject zephyr. EPSS 0.1% estimated probability of exploitation activity in the next 30 days.
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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.
Severity
- EPSS
- 0.1% estimated probability of exploitation activity in the next 30 days; 1st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-822 Untrusted Pointer Dereference
- Published
- Modified
- Assigned by
- zephyr (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| zephyrproject zephyr | from 3.7.0 before 4.3.2 |
| zephyrproject zephyr | from 4.4.0 before 4.5.0 |
Attack patterns (CAPEC)
- CAPEC-129 Pointer Manipulation Severity: Medium
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.