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TI-2026-58866 Aliases CVE-2026-86040

libp2p: Unbounded RPC decode + synchronous subscription processing in @libp2p/floodsub allows unauthenticated DoS

Priority MEDIUM 40CWE-400Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-400.

Summary

libp2p is a JavaScript implementation of the libp2p networking stack. Prior to 11.0.26, @libp2p/floodsub accepts unauthenticated RPC frames on /floodsub/1.0.0 through PeerStreams.attachInboundStream in packages/floodsub/src/peer-streams.ts without protobuf element limits, then processRpc and processRpcSubOpt in packages/floodsub/src/floodsub.ts synchronously process the subscriptions array without a per-frame cap. A single bounded-size frame can decode into millions of empty subscription entries that block the event loop, while hundreds of thousands of unique-topic SUBSCRIBE entries allocate PeerSet objects in this.topics that are not removed after peer removal or stop. Empty entries cause CPU exhaustion but do not grow this.topics; persistent memory growth requires unique topics. The subscription path bypasses message signature validation and the message-only processing queue, allowing a remote peer to cause sustained CPU denial of service, memory exhaustion, out-of-memory termination, and node unavailability. The issue is fixed in version 11.0.26.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0067 52nd percentileScored 2026-11-07
Fix Fixed js-libp2p (libp2p): 11.0.26floodsub (@libp2p): 11.0.26

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
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
libp2pjs-libp2pbefore 11.0.2611.0.26Patch availableCNA
libp2pfloodsubbefore 11.0.2611.0.26Patch availableCNA
  • js-libp2p Vendorlibp2p Affected before 11.0.26 Fixed in 11.0.26 Patch available CNA
  • floodsub Vendorlibp2p Affected before 11.0.26 Fixed in 11.0.26 Patch available CNA

Remediation

  • Fix · CNA js-libp2p (libp2p) Fixed in 11.0.26
  • Fix · CNA floodsub (@libp2p) Fixed in 11.0.26

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-86040
  2. 2026-11-06 Affected versions changed · Red Hat
  3. 2026-11-06 CVSS score added · Red Hat

References

Other 4

  • 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