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CVE-2026-81507

ESF-IDF: Bluetooth Classic L2CAP Heap Memory Disclosure Allowing Unauthorized Access to Sensitive Data

No known exploitation. EPSS puts it in the 17th percentile. No fix published yet.

CVSS 3.16.5MediumEPSS percentile17th0.3% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFixNone yetNo fix or workaround published

Published Updated Sources: CVE.org, NVD

NVD CVE.org

What to do

No fixed build or workaround is published yet. Limit exposure and watch for a patch.

  • Espressif Esp-idfAffected: < 5.2.8Upgrade to: not statedAffected: >= 5.3-beta1, < 5.3.6Upgrade to: not statedAffected: >= 5.4-beta1, < 5.5.5Upgrade to: not statedAffected: >= 6.0-beta1, < 6.0.3Upgrade to: not stated + 1 more branchStated by: CVE record

Versions as the sources state them. Full version matrix after sign-in

What it is

From the CVE record

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.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS17th
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.3% chance of exploitation activity in the next 30 days, which ranks it in the 17th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

5 events over 1 day, from the signal feeds we watch.

  1. Record updated
  2. Publishedweakness classified, att&ck mapped, record updated

Affected products

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Scored 6.5 by NVD.

How it is reached

  • Attack Vector AdjacentRequires access to the local network (e.g. same Wi-Fi, Bluetooth)
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality HighTotal information disclosure — all data in the component is compromised
  • Integrity NoneNo integrity impact
  • Availability NoneNo availability impact

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

References in the record

And 10 more references. See all after sign-in

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We'll flag the next CVE, public exploit or patch for Esp-idf, not every advisory.