CVE-2023-39533: libp2p nodes vulnerable to attack using large RSA keys

go-libp2p is the Go implementation of the libp2p Networking Stack. Prior to versions 0.27.8, 0.28.2, and 0.29.1 malicious peer can use large RSA keys to run a resource exhaustion attack & force a node to spend time doing signature verification of the large key. This vulnerability is present in the core/crypto module of go-libp2p and can occur during the Noise handshake and the libp2p x509 extension verification step. To prevent this attack, go-libp2p versions 0.27.8, 0.28.2, and 0.29.1 restrict RSA keys to <= 8192 bits. To protect one's application, it is necessary to update to these patch releases and to use the updated Go compiler in 1.20.7 or 1.19.12. There are no known workarounds for this issue.

— MITRE

libp2p go-libp2p is vulnerable to a denial of service, caused by a flaw during the signature verification. By sending a specially crafted request using large RSA keys, a remote attacker could exploit this vulnerability to exhaust available resource, and results in a denial of service condition.

libp2p nodes vulnerable to attack using large RSA keys

— Microsoft