CVE-2026-81507
What it is
ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. Prior to 5.2.8, 5.3.6, 5.5.5, 6.0.3, and 6.1-rc1, ESP-IDF BlueDroid L2CAP configuration-option processing in l2c_main.c and l2c_utils.c does not consistently validate option lengths against the remaining received packet bytes. A remote unauthenticated BR/EDR peer within radio range can send a malformed L2CAP configuration request that causes an out-of-bounds read, and under some runtime conditions limited adjacent Bluetooth stack memory can be included in an outbound L2CAP Configuration Response. The issue affects ESP32-class products using the BlueDroid host stack with Classic Bluetooth enabled. This issue is fixed in 5.2.8, 5.3.6, 5.5.5, 6.0.3, and 6.1-rc1.
At a glance
- Exploitability
- Can be exploited from the same network segment without logging in. High risk of data exposure.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 6.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-125 · Out-of-bounds read
- Record status
- Awaiting Analysis
Attack profile CVSS 3.1 · 6.5
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Raw vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-81507.md and follow it. Check whether this project is affected by CVE-2026-81507. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/espressif/esp-idf/commit/14c99559b4337cabcf0f09c21d16b93c4cd7a6fe
- https://github.com/espressif/esp-idf/commit/1e07f6d83ca892630a7210df2958455f7ca77b4a
- https://github.com/espressif/esp-idf/commit/5731c63ece128f156939b9f734256e2227c1442a
- https://github.com/espressif/esp-idf/commit/8de265dc44b1b22c749ea44ee7c609b3da4162f0
- https://github.com/espressif/esp-idf/commit/9a6d04f65e0e341e7d72bd417c9f31b8a04ce846
- https://github.com/espressif/esp-idf/commit/c2610255a5adce651ca582bb82368c3dd0ee2834
- https://github.com/espressif/esp-idf/commit/c8cd8f4f3019ae2f912c8cbe9974445e8d9b8749
- https://github.com/espressif/esp-idf/releases/tag/v5.2.8
- https://github.com/espressif/esp-idf/releases/tag/v5.3.6
- https://github.com/espressif/esp-idf/releases/tag/v5.5.5
References
- https://github.com/espressif/esp-idf/commit/14c99559b4337cabcf0f09c21d16b93c4cd7a6fe
- https://github.com/espressif/esp-idf/commit/1e07f6d83ca892630a7210df2958455f7ca77b4a
- https://github.com/espressif/esp-idf/commit/5731c63ece128f156939b9f734256e2227c1442a
- https://github.com/espressif/esp-idf/commit/8de265dc44b1b22c749ea44ee7c609b3da4162f0
- https://github.com/espressif/esp-idf/commit/9a6d04f65e0e341e7d72bd417c9f31b8a04ce846
- https://github.com/espressif/esp-idf/commit/c2610255a5adce651ca582bb82368c3dd0ee2834
- https://github.com/espressif/esp-idf/commit/c8cd8f4f3019ae2f912c8cbe9974445e8d9b8749
- https://github.com/espressif/esp-idf/releases/tag/v5.2.8
- https://github.com/espressif/esp-idf/releases/tag/v5.3.6
- https://github.com/espressif/esp-idf/releases/tag/v5.5.5
- https://github.com/espressif/esp-idf/releases/tag/v6.0.3
- https://github.com/espressif/esp-idf/releases/tag/v6.1-rc1
- https://github.com/espressif/esp-idf/security/advisories/GHSA-v335-fxwc-rc44