---
id: CVE-2026-95859
title: 'libp2p-rust: Gossipsub GRAFT topics unbounded growth'
summary: >-
  libp2p-rust is the official Rust language implementation of the libp2p
  networking stack. Prior to 0.49.5, Gossipsub GRAFT control-message handling
  unconditionally adds attacker-supplied topic hashes to connected_peer.topics
  without confi…
severity: high
cvss: 8.7
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-770
vendor: libp2p
product: rust-libp2p
affected:
  - rust-libp2p < 0.49.5
published: '2026-10-16'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:19:04.504Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-95859'
references:
  - url: >-
      https://github.com/libp2p/rust-libp2p/security/advisories/GHSA-g3g5-x568-qvqx
    label: >-
      https://github.com/libp2p/rust-libp2p/security/advisories/GHSA-g3g5-x568-qvqx
  - url: 'https://github.com/libp2p/rust-libp2p/pull/6608'
    label: 'https://github.com/libp2p/rust-libp2p/pull/6608'
  - url: >-
      https://github.com/libp2p/rust-libp2p/commit/51ed5f00e1b0620ded3444ecadf18477052148ea
    label: >-
      https://github.com/libp2p/rust-libp2p/commit/51ed5f00e1b0620ded3444ecadf18477052148ea
tags:
  - cve.org
ingestedAt: '2026-10-16T17:24:46.653Z'
---

## Overview

libp2p-rust is the official Rust language implementation of the libp2p networking stack. Prior to 0.49.5, Gossipsub GRAFT control-message handling unconditionally adds attacker-supplied topic hashes to connected_peer.topics without confirming that the peer previously subscribed to those topics. A remote unauthenticated peer that can reach a Gossipsub listener can repeatedly send novel GRAFT topics, causing cumulative per-peer memory growth that is not bounded by subscription filters, peer scoring, or per-message size limits. This can exhaust process memory and cause a denial of service. This issue is fixed in version 0.49.5.

## Affected

- `rust-libp2p < 0.49.5`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.