CVE-2026-10685

Memory corruption via callback after subscription release

Published Jul 31, 2026 · Updated Jul 31, 2026

Use-after-free in the Bluetooth GATT client in Zephyr RTOS before 4.5.0 allows physically proximate attackers to corrupt memory via an ATT Error Response. The gatt_write_ccc_rsp handler calls notify with NULL, returns the subscription parameters to the application, and then dereferences them to invoke subscribe. Exposure requires a connected GATT server peer and an application that frees or recycles the parameters; the resulting indirect call corrupts memory, crashes the device, or redirects control flow.

CVSS severity7.6
High
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Bluetooth GATT client in Zephyr RTOS before 4.5.0 allows physically proximate attackers to corrupt memory via an ATT Error Response. The gatt_write_ccc_rsp handler calls notify with NULL, returns the subscription parameters to the application, and then dereferences them to invoke subscribe. Exposure requires a connected GATT server peer and an application that frees or recycles the parameters; the resulting indirect call corrupts memory, crashes the device, or redirects control flow.

The record

CVE
CVE-2026-10685
Published
Jul 31, 2026
Updated
Jul 31, 2026
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-416, T1203
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 31, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.4.0 <4.5.0

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=2.4.0 <4.5.0

Published CVSS scores

7.6Zephyr ProjectCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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