Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 0.27% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-54167High confidence
Pipelines-as-Code GitHub App token request can be redirected via untrusted Enterprise Host header
tektoncd · pipelines-as-code
Official source article: GitHub GHSA-F5F4-3HH4-F54M ↗. Check the applicable product and release in the original source.
8.2HighCVSS 3.1
Patch only the product branches with a verified fix
Fix availability varies by productHigh technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 5 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:High, unchanged from published severity.unchanged
Compensating controls
- Apply the linked authoritative mitigation while planning the permanent fix.
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs tektoncd pipelines-as-code and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 5 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
- Red Hat Product Security: 5 affected or under-investigation product states without a fixed product state in the same current advisory
Open-source package ranges4 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 |
|---|---|---|---|
| gogithub.com/openshift-pipelines/pipelines-as-code | >= 0.43.0, < 0.48.0 | 0.48.0 | GitHub advisory ↗upstream repository advisory · 20 Aug 2026 |
| gogithub.com/openshift-pipelines/pipelines-as-code | >= 0.40.0, < 0.42.1 | 0.42.1 | GitHub advisory ↗upstream repository advisory · 20 Aug 2026 |
| gogithub.com/openshift-pipelines/pipelines-as-code | >= 0.38.0, < 0.39.6 | 0.39.6 | GitHub advisory ↗upstream repository advisory · 20 Aug 2026 |
| gogithub.com/openshift-pipelines/pipelines-as-code | < 0.37.8 | 0.37.8 | GitHub advisory ↗upstream repository advisory · 20 Aug 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-2026-54167 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitygithub.com/openshift-pipelines/pipelines-as-code: Pipelines-as-Code: GitHub App token redirection via untrusted host header
The vendor explicitly identifies these products as affected by this CVE.
- openshift-pipelines/pipelines-operator-proxy-rhel8 as a component of OpenShift Pipelines
- openshift-pipelines/pipelines-operator-proxy-rhel9 as a component of OpenShift Pipelines
- openshift-pipelines/pipelines-pipelines-as-code-controller-rhel8 as a component of OpenShift Pipelines
- openshift-pipelines/pipelines-rhel9-operator as a component of OpenShift Pipelines
- web-terminal/web-terminal-tooling-rhel9 as a component of Red Hat Web Terminal
- Summary
- A flaw was found in Pipelines-as-Code. The GitHub App provider incorrectly processes webhook events by accepting an untrusted X-GitHub-Enterprise-Host header as the API host before validating the webhook signature. An unauthenticated attacker can exploit this by sending a specially crafted webhook request, causing the system to send a locally signed GitHub App JSON Web Token (JWT) to an attacker-controlled service. This exposed JWT could then be used to attempt to generate installation access tokens, potentially leading to unauthorized access or actions within the GitHub App installation.
- Remediation
- Until a patched release is deployed, block or strip unexpected X-GitHub-Enterprise-Host headers at the ingress or proxy in front of the Pipelines-as-Code webhook endpoint. For GitHub.com installations, reject requests containing this header; for GitHub Enterprise Server, permit only the expected hostname. Restrict webhook access to trusted Git provider sources where possible, and rotate the GitHub App private key if compromise is suspected.
High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 5 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product01
What, why and how
Pipelines-as-Code is a CI/CD system that lets users define Tekton pipelines in source code repositories. Prior to 0.37.8, 0.39.6, 0.42.1, and 0.48.0, the GitHub App provider accepts X-GitHub-Enterprise-Host as the API host while processing webhook events containing an installation.id, before webhook signature validation or confirmation that the host matches the repository URL in the signed payload. An unauthenticated attacker who can reach the webhook endpoint can select an attacker-controlled host and cause the controller to send a locally signed GitHub App JWT to that service. The exposed JWT may be used to attempt to mint installation access tokens during its validity window, subject to the GitHub App installation and permissions. The incoming webhook installation-lookup path is also affected, but exploitation of that path requires the valid incoming webhook secret for the target Repository CR. This issue is fixed in versions 0.37.8, 0.39.6, 0.42.1, and 0.48.0.
What
Pipelines-as-Code is a CI/CD system that lets users define Tekton pipelines in source code repositories. Prior to 0.37.8, 0.39.6, 0.42.1, and 0.48.0, the GitHub App provider accepts X-GitHub-Enterprise-Host as the API host while processing webhook events containing an installation.id, before webhook signature validation or confirmation that the host matches the repository URL in the signed payload. An unauthenticated attacker who can reach the webhook endpoint can select an attacker-controlled host and cause the controller to send a locally signed GitHub App JWT to that service. The exposed JWT may be used to attempt to mint installation access tokens during its validity window, subject to the GitHub App installation and permissions. The incoming webhook installation-lookup path is also affected, but exploitation of that path requires the valid incoming webhook secret for the target Repository CR. This issue is fixed in versions 0.37.8, 0.39.6, 0.42.1, and 0.48.0.
Why
The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.
How
An attacker operating through a network path 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
Pipelines-as-Code is a CI/CD system that lets users define Tekton pipelines in source code repositories. Prior to 0.37.8, 0.39.6, 0.42.1, and 0.48.0, the GitHub App provider accepts X-GitHub-Enterprise-Host as the API host while processing webhook events containing an installation.id, before webhook signature validation or confirmation that the host matches the repository URL in the signed payload. An unauthenticated attacker who can reach the webhook endpoint can select an attacker-controlled host and cause the controller to send a locally signed GitHub App JWT to that service. The exposed JWT may be used to attempt to mint installation access tokens during its validity window, subject to the GitHub App installation and permissions. The incoming webhook installation-lookup path is also affected, but exploitation of that path requires the valid incoming webhook secret for the target Repository CR. This issue is fixed in versions 0.37.8, 0.39.6, 0.42.1, and 0.48.0.
Why
The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.
How
An attacker operating through a network path 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 None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Insufficient Verification of Data Authenticity → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- 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-345 ↗
CWE-345: Insufficient Verification of Data Authenticity. The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a 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.CHighConfidentiality impact: A successful attack can cause a major 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
- Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
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. - Fix availability varies by product
- Affected
- openshift-pipelines/pipelines-operator-proxy-rhel8 as a component of OpenShift Pipelines
- openshift-pipelines/pipelines-operator-proxy-rhel9 as a component of OpenShift Pipelines
- openshift-pipelines/pipelines-pipelines-as-code-controller-rhel8 as a component of OpenShift Pipelines
- openshift-pipelines/pipelines-rhel9-operator as a component of OpenShift Pipelines
- web-terminal/web-terminal-tooling-rhel9 as a component of Red Hat Web Terminal
- Action
- Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
- Workaround
- Until a patched release is deployed, block or strip unexpected X-GitHub-Enterprise-Host headers at the ingress or proxy in front of the Pipelines-as-Code webhook endpoint. For GitHub.com installations, reject requests containing this header; for GitHub Enterprise Server, permit only the expected hostname. Restrict webhook access to trusted Git provider sources where possible, and rotate the GitHub App private key if compromise is suspected.
04
Evidence and provenance
Published 15 Sept 2026 · Last source change 15 Sept 2026, 14:49 UTC · CWE-345 · Insufficient Verification of Data Authenticity
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-09-16
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-78587
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD awaiting enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- openshift-pipelines/pipelines-operator-proxy-rhel9 as a component of OpenShift Pipelines; openshift-pipelines/pipelines-rhel9-operator as a component of OpenShift Pipelines; web-terminal/web-terminal-tooling-rhel9 as a component of Red Hat Web Terminal
- After
- openshift-pipelines/pipelines-operator-proxy-rhel8 as a component of OpenShift Pipelines; openshift-pipelines/pipelines-operator-proxy-rhel9 as a component of OpenShift Pipelines; openshift-pipelines/pipelines-pipelines-as-code-controller-rhel8 as a component of OpenShift Pipelines; openshift-pipelines/pipelines-rhel9-operator as a component of OpenShift Pipelines; web-terminal/web-terminal-tooling-rhel9 as a component of Red Hat Web Terminal
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- web-terminal/web-terminal-tooling-rhel9 as a component of Red Hat Web Terminal
- After
- openshift-pipelines/pipelines-operator-proxy-rhel9 as a component of OpenShift Pipelines; openshift-pipelines/pipelines-rhel9-operator as a component of OpenShift Pipelines; web-terminal/web-terminal-tooling-rhel9 as a component of Red Hat Web Terminal
- ENISA EUVD mappingEUVD-2026-78587 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-78587"}
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
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.