---
title: "GHSA-9v8h-qqgm-4m35: Brotli: Out-of-bounds write in the Brotli decoder (\"Node2Shell\") also affects the PyPI Brotli package"
url: https://erroneo.us/security/ghsa/GHSA-9v8h-qqgm-4m35/
description: "GHSA-9v8h-qqgm-4m35 (critical, PyPI): Brotli: Out-of-bounds write in the Brotli decoder (\"Node2Shell\") also affects the PyPI Brotli package. A buffer…"
type: advisory
section: "Security Digest"
date_published: 2026-10-22
date_modified: 2026-10-23
publisher: erroneo.us
author: erroneo.us Security Desk
ghsa: "GHSA-9v8h-qqgm-4m35"
license: All rights reserved. Quote with attribution and a link.
---

# GHSA-9v8h-qqgm-4m35: Brotli: Out-of-bounds write in the Brotli decoder ("Node2Shell") also affects the PyPI Brotli package

## Affected packages

- PyPI `brotli` >= 1.0.3, < 1.2.1 → fixed: 1.2.1
- PyPI `brotlicffi` >= 1.0.3, < 1.2.1.0 → fixed: 1.2.1.0

## Details

A buffer overflow vulnerability in the Brotli decoder (c/dec/decode.c) in Google Brotli versions 1.0.3 through 1.2.0 on all platforms allows a remote unauthenticated attacker to corrupt adjacent decoder state memory, disclose sensitive memory contents, cause a denial of service, or potentially execute arbitrary code using a crafted Brotli-compressed stream. Users need to update any Brotli libraries or binaries between 1.0.3 through 1.2.0 to the latest available version: 1.0.10 or 1.1.1 or 1.2.1.

## Sources

- [GitHub Advisory GHSA-9v8h-qqgm-4m35](https://github.com/advisories/GHSA-9v8h-qqgm-4m35)
- [nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-111497)
- [nodejs.org](https://nodejs.org/en/blog/vulnerability/october-2026-security-releases#nodejs-brotli-decoder-out-of-bounds-write-permits-remote-code-execution-cve-2026-111497---high)
- [github.com](https://github.com/google/brotli/commit/0ed4268a4401abcb4472096340477cf4af7d1a2b)
- [github.com](https://github.com/google/brotli/commit/50a9b70a4d5e1443fc40927952276b68fffa83a0)
- [github.com](https://github.com/google/brotli/commit/b418fa81c48262a86a95332b0bc6d62c30aa78b6)
- [github.com](https://github.com/google/brotli/commit/da9806362874b9bd4b552a3af360b5d6347beb12)
- [github.com](https://github.com/google/brotli/releases/tag/v1.0.10)
- [github.com](https://github.com/google/brotli/releases/tag/v1.1.1)
- [github.com](https://github.com/google/brotli/releases/tag/v1.2.1)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/brotli/PYSEC-2026-4322.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/brotlicffi/PYSEC-2026-4323.yaml)
- [nodejs.org](https://nodejs.org/en/blog/vulnerability/october-2026-security-releases)
- [opensourcemalware.com](https://opensourcemalware.com/blog/node2shell-affects-python)
- [pypi.org](https://pypi.org/project/Brotli)
- [pypi.org](https://pypi.org/project/brotlicffi)
- [cve.org](https://www.cve.org/CVERecord?id=CVE-2026-111497)

---
Source page: https://erroneo.us/security/ghsa/GHSA-9v8h-qqgm-4m35/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt