# CVE-2026-81508: ESF-IDF: Heap Out-of-Bounds Read in Bluedroid A2DP Sink Media Packet Processing

> A remote attacker with radio proximity can trigger an out-of-bounds read in the A2DP sink, potentially disclosing limited heap memory contents.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Sep 2026
- **Updated:** 24 Sep 2026
- **Also known as:** GHSA-xcpr-5mqp-9qvv

## What is CVE-2026-81508?

CVE-2026-81508 is a medium-severity vulnerability in espressif esp-idf, published on 24 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In 5.5.5, 6.0.1, and 6.1, the BlueDroid A2DP sink function btc_a2dp_sink_handle_inc_media() reads a timestamp field from the received media buffer before validating that the packet layout contains the field. A paired BR/EDR audio source within radio range can send a malformed A2DP media packet to a build with BlueDroid Classic Bluetooth and A2DP sink support enabled, causing an out-of-bounds read into adjacent heap memory and limited disclosure of heap contents. Arbitrary memory disclosure and code execution are not established.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-81508?


## How do I fix CVE-2026-81508?

No fix has been published for CVE-2026-81508 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-81508 being exploited?

There is no known exploitation of CVE-2026-81508 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-81508 and fix it if it is affected.

What it is: CVE-2026-81508 is a medium-severity vulnerability in espressif esp-idf, published on 24 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-81508 in the wild and no public exploit code.

Affected product: espressif esp-idf. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-81508/ (Markdown: https://insights.sbomify.com/CVE-2026-81508/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-81508
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-81508
- OSV: https://osv.dev/vulnerability/CVE-2026-81508

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-81508/
Summaries are generated and may contain mistakes; the official description above is the record.