What’s Vulnerable › Vulnerabilities

CVE-2025-8556: Github.com/cloudflare/circl: circl-fourq: missing and wrong validation can lead to incorrect results

• Severity: low (CVSS 3.7 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-08-06 · updated 2026-10-27
• Weakness: CWE-1287

Description

A flaw was found in CIRCL's implementation of the FourQ elliptic curve. This vulnerability allows an attacker to compromise session security via low-order point injection and incorrect point validation during Diffie-Hellman key exchange.

Affected products

• circl: before 1.6.1 — fixed in 1.6.1
• Red Hat Advanced Cluster Management for Kubernetes 2: all versions
• Red Hat Builds for Red Hat OpenShift: all versions
• Red Hat Custom Metric Autoscaler operator for Red Hat Openshift: all versions
• Red Hat Multicluster Global Hub: all versions
• Red Hat OpenShift Container Platform 4.18: all versions
• Red Hat OpenShift Pipelines: all versions
• Red Hat OpenShift Serverless: all versions
• Red Hat OpenShift Service Mesh 3: all versions
• Red Hat Advanced Cluster Security 4: all versions
• Red Hat Ceph Storage 5: all versions
• Red Hat Ceph Storage 6: all versions
• Red Hat Ceph Storage 8: all versions
• Red Hat Developer Hub 1: all versions
• Red Hat Edge Manager preview: all versions
• Red Hat Enterprise Linux AI (RHEL AI): all versions
• Red Hat OpenShift AI (RHOAI): all versions
• Red Hat OpenShift Dev Workspaces Operator: all versions
• Red Hat OpenShift for Windows Containers: all versions
• Red Hat OpenShift GitOps: all versions
• Red Hat OpenShift Virtualization 4: all versions
• Red Hat Trusted Application Pipeline: all versions
• Red Hat Trusted Artifact Signer: all versions
• Red Hat Trusted Profile Analyzer: all versions

How to fix

Upgrade to a fixed version: circl 1.6.1. Check the vendor advisory for mitigations.

References

• https://access.redhat.com/security/cve/CVE-2025-8556
• https://bugzilla.redhat.com/show_bug.cgi?id=2371624
• https://github.com/cloudflare/circl
• https://github.com/cloudflare/circl/security/advisories/GHSA-2x5j-vhc8-9cwm
• https://github.com/cloudflare/circl/tree/v1.6.1
• https://news.ycombinator.com/item?id=45669593
• https://www.botanica.software/blog/cryptographic-issues-in-cloudflares-circl-fourq-implementation

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