libp2p libp2p-rust up to 0.49.4 Gossipsub denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k2.71-

Summaryinfo

A vulnerability was found in libp2p libp2p-rust up to 0.49.4. It has been rated as problematic. This impacts an unknown function of the component Gossipsub. This manipulation causes denial of service. The identification of this vulnerability is CVE-2026-95859. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic was found in libp2p libp2p-rust up to 0.49.4. Affected by this vulnerability is an unknown function of the component Gossipsub. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-95859 since 09/22/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 0.49.5 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libp2p-rust 0.49.5

Timelineinfo

09/22/2026 CVE reserved
10/16/2026 +24 days Advisory disclosed
10/16/2026 +0 days VulDB entry created
10/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-95859 (🔒)
GCVE (CVE): GCVE-0-2026-95859
GCVE (VulDB): GCVE-100-421309

Entryinfo

Created: 10/16/2026 17:46
Changes: 10/16/2026 17:46 (67)
Complete: 🔍
Cache ID: 216::103

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