high7.5

CVE-2023-39533

libp2p nodes vulnerable to attack using large RSA keys

Impact

### Impact A 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 now restricts RSA keys to <= 8192 bits. ### Patches Users should upgrade their go-libp2p versions to >=v0.27.8, >= v0.28.2, or >=v0.29.1 To protect your application, it's necessary to update to these patch releases **AND** to use the updated Go compiler (1.20.7 or 1.19.12, respectively) ### Workarounds There are no known workarounds ### References The Golang crypto/tls package also had this vulnerability ("verifying certificate chains containing large RSA keys is slow” https://github.com/golang/go/issues/61460) Fix in golang/go crypto/tls: https://github.com/golang/go/commit/2350afd2e8ab054390e284c95d5b089c142db017 Fix in quic-go https://github.com/quic-go/quic-go/pull/4012

Affected packages

Ecosystem	Package	Affected	Fixed in
go	`github.com/libp2p/go-libp2p`	< 0.27.8	0.27.8

Affected products

Vendor	Product	Affected versions
Libp2p	Go-Libp2p	before 0.27.8 from 0.28.0 before 0.28.2 Version 0.29.0

Weakness classification

CWE-770