Skip to content
Fencer Vulns
high 7.5

CVE-2023-39533 json

libp2p nodes vulnerable to attack using large RSA keys

published 2023-08-08 3 y ago modified 2026-09-01 2 mo ago also GHSA-876p-8259-xjgg , GO-2023-2000 , EUVD-2023-2242

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.5%
EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits
0
none known

Summary

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.

Patch / fix

  • go github.com/libp2p/go-libp2p 0.27.8, 0.28.2, 0.29.1
  • libp2p go-libp2p 0.27.8, 0.28.2
  • golang CBL-Mariner 2.0, Azure Linux 3.0 1.19.12-1
  • msft-golang CBL-Mariner 2.0 1.19.12-1
  • golang CBL-Mariner 2.0 1.21.6-1

azure linux advisories AZL-27872AZL-27875AZL-37359AZL-37422AZL-52773

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-39533 updated cvss 7.5

go-libp2p: libp2p nodes vulnerable to attack using large RSA keys

  • Red Hat OpenShift Container Platform 4 openshift, openshift-clients, openshift-kubelet, openshift-hyperkube, openshift-kube-apiserver, openshift-kube-scheduler, +2 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
2 y ago

Exploit prediction

1.51% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/libp2p/go-libp2p/pull/2454 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
go github.com/libp2p/go-libp2p
<0.27.8
>=0.28.0, <0.28.2
>=0.29.0, <0.29.1
0.27.8
0.28.2
0.29.1

Affected products

  • libp2p go-libp2p

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.