Evidence used
- No CISA KEV confirmation is currently recorded.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 3.60% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2020
CVE-2020-8558High confidence
Kubernetes node setting allows for neighboring hosts to bypass localhost boundary
Kubernetes · Kubernetes
5.4MediumCVSS 3.1
Within 7 days
Patch availableMedium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Medium, unchanged from published severity.unchanged
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
- Confirm that the asset runs Kubernetes Kubernetes and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Distribution package intelligence
4 package statesRelease-specific package status
Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
Repository candidate not checked
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Distribution release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Debian trixietrixie · source | kubernetes | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.18.5-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian bookwormbookworm · source | kubernetes | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.18.5-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian forkyforky · source | kubernetes | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.18.5-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
| Debian sidsid · source | kubernetes | Vendor fix publishedDebian records a fixed source-package version for this release. | 1.18.5-1 | Debian Security Tracker ↗Source updated 23 Oct 2026 |
Open-source package ranges3 source-attributed ranges
These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.
| Ecosystem and package | Affected range | First fixed version | Evidence |
|---|---|---|---|
| Gok8s.io/kubernetes | SEMVER: introduced 1.18.0; fixed 1.18.4 | 1.18.4 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Gok8s.io/kubernetes | SEMVER: introduced 1.17.0; fixed 1.17.7 | 1.17.7 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Gok8s.io/kubernetes | SEMVER: introduced 0; fixed 1.16.11 | 1.16.11 | OSV record ↗aggregator derived · 10 Sep 2026 |
Direct vendor intelligence
1 currentAuthoritative vendor CSAF and VEX advisories
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
CVE-2020-8558 · CSAF 2.0 · revision 14 · interimSUSE Product Security TeamCVE-2020-8558
The vendor recommends these product versions as the target state.
- govulncheck-vulndb-0.0.20250814T182633-160000.1.2 as component of SUSE Linux Enterprise Server 16.0
- govulncheck-vulndb-0.0.20260916T180043-160100.1.1 as component of SUSE Linux Enterprise Server 16.1
- govulncheck-vulndb-0.0.20250814T182633-160000.1.2 as component of SUSE Linux Enterprise Server for SAP applications 16.0
- govulncheck-vulndb-0.0.20260916T180043-160100.1.1 as component of SUSE Linux Enterprise Server for SAP applications 16.1
- govulncheck-vulndb-0.0.20250807T150727-1.1 as component of openSUSE Tumbleweed
- Summary
- The Kubelet and kube-proxy components in versions 1.1.0-1.16.10, 1.17.0-1.17.6, and 1.18.0-1.18.3 were found to contain a security issue which allows adjacent hosts to reach TCP and UDP services bound to 127.0.0.1 running on the node or in the node's network namespace. Such a service is generally thought to be reachable only by other processes on the same host, but due to this defeect, could be reachable by other hosts on the same LAN as the node, or by containers running on the same node as the service.
- Remediation
- To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available01
What, why and how
The Kubelet and kube-proxy components in versions 1.1.0-1.16.10, 1.17.0-1.17.6, and 1.18.0-1.18.3 were found to contain a security issue which allows adjacent hosts to reach TCP and UDP services bound to 127.0.0.1 running on the node or in the node's network namespace. Such a service is generally thought to be reachable only by other processes on the same host, but due to this defeect, could be reachable by other hosts on the same LAN as the node, or by containers running on the same node as the service.
What
The Kubelet and kube-proxy components in versions 1.1.0-1.16.10, 1.17.0-1.17.6, and 1.18.0-1.18.3 were found to contain a security issue which allows adjacent hosts to reach TCP and UDP services bound to 127.0.0.1 running on the node or in the node's network namespace. Such a service is generally thought to be reachable only by other processes on the same host, but due to this defeect, could be reachable by other hosts on the same LAN as the node, or by containers running on the same node as the service.
Why
The product protects a primary channel, but it does not use the same level of protection for an alternate channel.
How
An attacker operating through an adjacent network may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
The Kubelet and kube-proxy components in versions 1.1.0-1.16.10, 1.17.0-1.17.6, and 1.18.0-1.18.3 were found to contain a security issue which allows adjacent hosts to reach TCP and UDP services bound to 127.0.0.1 running on the node or in the node's network namespace. Such a service is generally thought to be reachable only by other processes on the same host, but due to this defeect, could be reachable by other hosts on the same LAN as the node, or by containers running on the same node as the service.
Why
The product protects a primary channel, but it does not use the same level of protection for an alternate channel.
How
An attacker operating through an adjacent network may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material Reference recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
- Likely attack path
- an adjacent network → Unprotected Alternate Channel → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Adjacent
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-420 ↗
CWE-420: Unprotected Alternate Channel. The product protects a primary channel, but it does not use the same level of protection for an alternate channel.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVAdjacentAttack vector: The attacker must be on an adjacent or logically close network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Action
- To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Workaround
- A mitigation or workaround reference is available from the source linked below; validate it against the affected product and version.
04
Evidence and provenance
Published 27 Jul 2020 · Last source change 16 Sept 2024, 22:40 UTC · CWE-420 · Unprotected Alternate Channel
CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2022-1237
Product sourceCNA
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.