HighCVE-2026-54167

    Pipelines-as-Code GitHub App token request can be redirected via untrusted Enterprise Host header (CVE-2026-54167)

    Published Last modified Sources: OSV, CVE.org, Hersteller

    Share

    What is affected, what to do

    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.

    Update Tektoncd Pipelines-as-code to version 0.37.8.

    Affected
    • Tektoncd Pipelines-as-code gte 0.38.0, < 0.39.6..*
    • Tektoncd Pipelines-as-code lt *..0.37.8
    Fixed in
    • Tektoncd Pipelines-as-code 0.37.8

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    8.2

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: Vendor (CNA), CVSS v3

    8.2

    CVSS v3

    Severity High on the scale from 0 to 10.

    Source: OSV, CVE.org, Hersteller

    0.3 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 19.1

    Show all metrics
    Severity
    High
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    69.88 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    no public PoC known
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    8.2 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    8.2
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    0.3 %
    Low — model estimates < 1% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    19.1
    Elevated — this CVE ranks above at least 10% of all CVEs scored today.
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published
    CISA assessment (SSVC)
    Exploitation: none known · automatable · Technical impact: partial
    Source: CISA Vulnrichment, as of 15 September 2026
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-345

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    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.

    Source: OSV (Open Source Vulnerabilities), NVD (NIST), CVE.org (MITRE), GitHub Security Advisories, cvelistv5

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    tektoncdpipelines-as-code
    • ≥ 0.38.0, < 0.39.6
    • < 0.37.8
    • —
    • 0.37.8
    gogithub.com/openshift-pipelines/pipelines-as-code
    • 0.38.0
    • —
    • 0.40.0
    • 0.43.0
    • 0.39.6
    • 0.37.8
    • 0.42.1
    • 0.48.0

    Vendors and products

    Weakness classes (CWE)

    • CWE-345Insufficient Verification of Data Authenticity

      Class

      The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.

      Entry at MITRE CWE-345

    References & sources

    • github.comtektoncd/pipelines-as-code/security/advisories/GHSA-f5f4-3hh4-f…web, x_refsource_CONFIRM
    • github.comtektoncd/pipelines-as-codepackage
    • github.comtektoncd/pipelines-as-code/commit/402d5c7eeece881cb082ec68e9e8b…x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/commit/40813976a77920feaf52671320d6d…x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/commit/ac6fded6dfb69ade7197d4eeed6e9…x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/commit/e0c4a11ea3800ab9d26cf3a8ae92b…x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/releases/tag/v0.37.8x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/releases/tag/v0.39.6x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/releases/tag/v0.42.1x_refsource_MISC, web
    • github.comtektoncd/pipelines-as-code/releases/tag/v0.48.0x_refsource_MISC, web
    • NVD (NIST)vuln/detail/CVE-2026-54167advisory
    • github.comtektoncd/pipelines-as-code/pull/2759web

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. ReceivedGitHub

      CVSS V3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

      Weakness type: CWE-345

      Description added or changed

      Show 13 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionadded
      —
      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.
      CVSSadded
      —
      AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
      Weakness type (CWE)added
      —
      CWE-345
      Affected versions (publisher)added
      —
      New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/54xxx/CVE-2026-54167.json">CVE-2026-54167</a>
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/commit/402d5c7eeece881cb082ec68e9e8b61709e39ace
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/commit/40813976a77920feaf52671320d6d3c5ff08eb7e
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/commit/ac6fded6dfb69ade7197d4eeed6e90ddbe1b79bc
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/commit/e0c4a11ea3800ab9d26cf3a8ae92b74cf18527c3
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/releases/tag/v0.37.8
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/releases/tag/v0.39.6
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/releases/tag/v0.42.1
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/releases/tag/v0.48.0
      Referenceadded
      —
      https://github.com/tektoncd/pipelines-as-code/security/advisories/GHSA-f5f4-3hh4-f54m

      Source identifier: security-advisories@github.com

    2. Record modifiedCISA ADP

      CISA assessment (SSVC): exploitation: none known, automatable: yes

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      SSVC assessmentadded
      —
      {"id":"CVE-2026-54167","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-09-15T14:49:51.787044Z"}

      Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Embed badge

    Show the severity and KEV status of this vulnerability on your site – with a link back here. The image is updated hourly.

    Badge preview for CVE-2026-54167
    <a href="https://intel.neosec.eu/en/cve/CVE-2026-54167"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-54167.svg?lang=en" alt="CVE-2026-54167 – NEOSEC Intel" height="20"></a>