CVE-2018-9456 is a high severity out-of-bounds read caused by an incorrect bounds check in the Bluetooth service discovery code (sdpu_extract_attr_seq in sdp_utils.cc). NVD scores it 7.5. Google fixes it at security patch level 2018-09-01 or later. Install the device update that reaches that level.
What's affected
- Product: Android, in the Bluetooth service discovery code (sdpu_extract_attr_seq in sdp_utils.cc).
- Releases listed by the bulletin: 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 2018-09-01 or later, according to the Android Security Bulletin for September 2018.
- Impact in the record: remote denial of service with no privileges and no user interaction.
- Severity: NVD scores it 7.5 High (vector AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H). The bulletin lists it as High, type DoS. The two ratings agree.
- Weakness classes: CWE-125 (Out-of-bounds Read).
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 2018-09-01 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 2018-09-01 or later. - For a fleet, export the patch level from your mobile device management console and filter for dates earlier than 2018-09-01.
- 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 2018-09-01 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
The only impact in the record is availability (A:H), with a 7.5 score. A device that crashes its Bluetooth process loses pairing and audio until it recovers, which matters for fleets of handsets used with headsets or in vehicles.
An incorrect bounds check lets a read run past the end of a buffer. When the read lands on unmapped memory, the process crashes. In a service that handles discovery requests from nearby devices, a crash that a remote peer can trigger is a denial of service. The record's KEV flag is false, so CISA does not list it as exploited. The bulletin says Google had no reports of active customer exploitation or abuse of the newly reported issues in it. That is the absence of a report in the sources read, not proof that no one has tried.
Quick check
Is data at risk here?
The record shows no confidentiality or integrity impact. It scores availability only. The bulletin calls the result denial of service.
Which patch level should I look for?
The Android Security Bulletin for September 2018 places this fix at 2018-09-01. Any date at or after 2018-09-01 includes it. Some makers ship it under a different update name, so check the date.
Sources
- Android Security Bulletin for September 2018: Affected releases, severity, type and the patch level that carries the fix.
Last reviewed: 19 October 2026.
