High severity · published Sep 17, 2026
CVE-2026-86039
libp2p: PeerStore accepts attacker-signed PeerRecords for a victim peer ID and stores certified attacker addresses
8.2
CVSS
0.3%
EPSS
No
On KEV
Description
libp2p is a JavaScript implementation of the libp2p networking stack. From 8.0.0 until 12.0.24, @libp2p/peer-store in packages/peer-store/src/index.ts uses consumePeerRecord to verify a RecordEnvelope signature but does not require PeerRecord.peerId in the signed payload to equal the signer peer ID derived by RecordEnvelope.openAndCertify. The expectedPeer option checks only the envelope signer, and the gossipsub Peer Exchange path can provide the attacker's own peer ID as expectedPeer. An attacker can therefore sign a record with the attacker's key, place a victim peer ID and attacker-controlled multiaddrs in the payload, and have certified addresses stored for the victim. The poisoned addresses can cause address-book corruption, dial redirection or failure, routing manipulation, and reachability disruption, although the connection upgrade still verifies remote peer identity and prevents a complete identity takeover. The issue is fixed in version 12.0.24.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 19% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JS
js-libp2p · libp2p
>= 8.0.0, < 12.0.24 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-86039
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-86039
github.com
https://github.com/libp2p/js-libp2p/commit/3bf5d395cbca1488eea6e87cd771e4613b661c30
github.com
https://github.com/libp2p/js-libp2p/pull/3570
github.com
https://github.com/libp2p/js-libp2p/releases/tag/peer-store-v12.0.24
github.com
https://github.com/libp2p/js-libp2p/security/advisories/GHSA-vrf4-mx87-p53w
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