# CVE-2026-87961: ESP32-audioI2S 3.4.4 through 4.0.0 Heap-based Out-of-Bounds Read via Shadowed Length Parameter in read_ID3_Header

> Attackers can crash ESP32 devices or leak heap memory by sending malicious MP3 files or audio streams to the ESP32-audioI2S library.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 10 Sep 2026
- **Updated:** 10 Sep 2026
- **Also known as:** GHSA-p79f-7v67-j5f7

## What is CVE-2026-87961?

CVE-2026-87961 is a high-severity memory corruption vulnerability in schreibfaul1 ESP32-audioI2S, published on 10 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

ESP32-audioI2S versions 3.4.4 through 4.0.0 contain a heap-based out-of-bounds read vulnerability in the read_ID3_Header function due to a shadowed length parameter in ID3 synchronized-lyrics processing. Attackers can craft malicious MP3 files or HTTP audio streams with oversized frame size declarations to read past allocated buffer boundaries, causing device crashes or exposing adjacent heap memory.

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

## Which versions are affected by CVE-2026-87961?


## How do I fix CVE-2026-87961?

No fix has been published for CVE-2026-87961 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-87961 being exploited?

There is no known exploitation of CVE-2026-87961 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-87961 and fix it if it is affected.

What it is: CVE-2026-87961 is a high-severity memory corruption vulnerability in schreibfaul1 ESP32-audioI2S, published on 10 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-87961 in the wild and no public exploit code.

Affected product: schreibfaul1 ESP32-audioI2S. 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-2026-87961/ (Markdown: https://insights.sbomify.com/CVE-2026-87961/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-87961
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-87961
- OSV: https://osv.dev/vulnerability/CVE-2026-87961

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-87961/
Summaries are generated and may contain mistakes; the official description above is the record.