CVE-2018-9414 is a high severity out-of-bounds stack write caused by a missing bounds check in the Bluetooth GATT server code (gattServerSendResponseNative in com_android_bluetooth_gatt.cpp). NVD scores it 7.8. Google fixes it at security patch level 2018-07-05 or later. Install the device update that reaches that level.
What's affected
- Product: Android, in the Bluetooth GATT server code (gattServerSendResponseNative in com_android_bluetooth_gatt.cpp).
- Releases listed by the bulletin: 6.0, 6.0.1, 7.0, 7.1.1, 7.1.2, 8.0 and 8.1. The NVD product list shows only some Android releases, so treat the bulletin as the fuller list.
- Fixed in: security patch level 2018-07-05 or later, according to the Pixel and Nexus Security Bulletin for July 2018.
- Impact in the record: local escalation of privilege, with user level execution privileges needed and no user interaction.
- Severity: NVD scores it 7.8 High (vector AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). The bulletin lists it as Moderate, type EoP. Both ratings are given because they differ.
- Weakness classes: CWE-787 (Out-of-bounds Write).
How to check if you're exposed
- On the device, open Settings and find the Android security patch level, usually under About phone. The exact path varies by manufacturer. A date earlier than 2018-07-05 means the fix is not present.
- With a USB debugging connection, run
adb shell getprop ro.build.version.security_patch. It prints the patch level as a date. You need 2018-07-05 or later. - For a fleet, export the patch level from your mobile device management console and filter for dates earlier than 2018-07-05.
- Match each device against the release list above. Devices on releases outside it are not named for this CVE, but check them against the other entries in the same bulletin.
What to do now
- Identify every Android device in scope and record its current security patch level.
- Roll out the manufacturer or carrier update that reaches 2018-07-05 or later. Google publishes the fixes, but each device maker decides when its devices receive them.
- For devices that no longer receive updates, plan replacement or limit what they can reach, such as corporate mail and internal apps.
- Until patched, turn Bluetooth off when you do not need it and avoid pairing with unknown devices. This lowers exposure but does not replace the update.
- Write the update policy down, with a maximum patch age, and report exceptions.
Why it matters
This one is local. An attacker needs to be running code on the device already, with ordinary user privileges (vector AV:L/PR:L). That makes it a second stage bug: it matters most when a malicious app has already landed.
Writing past the end of a stack buffer can overwrite saved control data. The function name points at code that sends responses for the GATT server. A privilege escalation here lets a limited app reach privileges it was never granted. The record's KEV flag is false, so CISA does not list it as exploited. That is the absence of a report in the sources read, not proof that no one has tried.
Quick check
Is this exploitable from across the room?
Not according to the record. The attack vector is local, so the weakness needs code already running on the device. Bluetooth proximity alone is not described as enough.
Which patch level should I look for?
The Pixel and Nexus Security Bulletin for July 2018 places this fix at 2018-07-05. Any date at or after 2018-07-05 includes it. Some makers ship it under a different update name, so check the date.
Sources
- Pixel and Nexus Security Bulletin for July 2018: Affected releases, severity, type and the patch level that carries the fix.
Last reviewed: 19 October 2026.
