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TI-2026-75360 Aliases CVE-2026-95859

Unbounded topic growth in rust-libp2p Gossipsub GRAFT handling

Priority LOW 37CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

The libp2p Rust implementation rust-libp2p is affected before 0.49.5. Gossipsub GRAFT handling adds attacker-supplied topic hashes to a connected peer's topic set without checking that the peer subscribed to them, a flaw classified as CWE-770. A remote unauthenticated peer that can reach a Gossipsub listener can repeatedly send new GRAFT topics, growing memory per peer without bound and exhausting process memory for a denial of service.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00291 21st percentileScored 2026-11-07
Fix Fixed rust-libp2p (libp2p): 0.49.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
libp2prust-libp2pbefore 0.49.50.49.5Patch availableCNA
  • rust-libp2p Vendorlibp2p Affected before 0.49.5 Fixed in 0.49.5 Patch available CNA

Remediation

Upgrade rust-libp2p to version 0.49.5, which fixes the issue.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA rust-libp2p (libp2p) Fixed in 0.49.5

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-95859
  2. 2026-10-18 Priority changed: MEDIUM → LOW
  3. 2026-10-21 CISA SSVC decision points changed
  4. 2026-11-06 Affected versions changed · Red Hat
  5. 2026-11-06 CVSS score added · Red Hat

References

Other 3

  • TI-2026-60386 libp2p-rendezvous through 0.17.1 Denial of Service via Unbounded Registration TTL in Discovery Responses CVSS 4.0HIGH 8.7
  • TI-2026-58865 libp2p: PeerStore accepts attacker-signed PeerRecords for a victim peer ID and stores certified attacker addresses CVSS 3.1HIGH 8.2
  • TI-2026-44102 libp2p-quic: Remote panic via certificate expiry race during QUIC handshake CVSS 4.0HIGH 8.2
  • TI-2026-27587 libp2p-rust has unbounded rendezvous DISCOVER cookies enable remote memory exhaustion CVSS 3.1HIGH 8.2
  • TI-2026-58864 libp2p: Gossipsub StrictSign accepts attacker-signed messages as a victim RSA peer ID CVSS 3.1HIGH 7.5
  • TI-2026-53982 libp2p: Circuit relay v2 server reservation refresh leaks abort listeners and allows remote resource exhaustion CVSS 3.1HIGH 7.5
See all 26 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences