Description
Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Prior to 1.11.1, the HTTP resolver's FetchHttpResource function calls io.ReadAll(resp.Body) with no response body size limit. Any tenant with permission to create TaskRuns or PipelineRuns that reference the HTTP resolver can point it at an attacker-controlled HTTP server that returns a very large response body within the 1-minute timeout window, causing the tekton-pipelines-resolvers pod to be OOM-killed by Kubernetes. Because all resolver types (Git, Hub, Bundle, Cluster, HTTP) run in the same pod, crashing this pod denies resolution service to the entire cluster. Repeated exploitation causes a sustained crash loop. The same vulnerable code path is reached by both the deprecated pkg/resolution/resolver/http and the current pkg/remoteresolution/resolver/http implementations. This vulnerability is fixed in 1.11.1.
Published: 2026-04-21
Score: 6.5 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Denial of Service via memory exhaustion
Action: Immediate Patch
AI Analysis

Impact

Tekton Pipelines’ HTTP resolver reads HTTP response bodies without a size limit, leading to uncontrolled memory consumption when a malicious server delivers a very large payload. The vulnerability resides in the FetchHttpResource function of both the deprecated and current HTTP resolver implementations. When an overlarge body is processed, the tekton‑pipelines‑resolvers pod is OOM‑killed, interrupting all resolver services and causing a cluster‑wide denial of service. The weakness is characterized by CWE‑400.

Affected Systems

All Tekton Pipeline installations using versions prior to 1.11.1 are affected, including every resolver type (Git, Hub, Bundle, Cluster, HTTP). Any tenant who can create TaskRuns or PipelineRuns has the authority to trigger the vulnerability by referencing an HTTP resolver pointed at a malicious endpoint.

Risk and Exploitability

The CVSS score of 6.5 indicates medium severity, and the lack of an EPSS score suggests there is no emerging widespread exploitation data. The vulnerability was not listed in CISA KEV. An attacker must have permissions to create TaskRuns or PipelineRuns; once privileged, they can induce the resolver pod to consume excessive memory and crash repeatedly, resulting in a sustained denial of service. The attack is cluster‑wide due to the shared resolver pod, but does not provide remote code execution or data exfiltration. The risk is primarily availability degradation.

Generated by OpenCVE AI on April 22, 2026 at 06:24 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade Tekton Pipelines to version 1.11.1 or later, which limits the HTTP response body size in the resolver.
  • If an upgrade is not immediately possible, restrict the creation of TaskRuns and PipelineRuns to trusted users or namespaces, and enforce strict quota limits on resolver pod memory to mitigate OOM effects.
  • Disable or remove the HTTP resolver from the cluster configuration during remediation to eliminate the attack surface until a patch is applied.

Generated by OpenCVE AI on April 22, 2026 at 06:24 UTC.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Github GHSA Github GHSA GHSA-m2cx-gpqf-qf74 Tekton Pipelines: HTTP Resolver Unbounded Response Body Read Enables Denial of Service via Memory Exhaustion
History

Wed, 22 Apr 2026 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 22 Apr 2026 04:00:00 +0000

Type Values Removed Values Added
First Time appeared Tektoncd
Tektoncd pipeline
Vendors & Products Tektoncd
Tektoncd pipeline

Wed, 22 Apr 2026 00:00:00 +0000

Type Values Removed Values Added
Description Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Prior to 1.11.1, the HTTP resolver's FetchHttpResource function calls io.ReadAll(resp.Body) with no response body size limit. Any tenant with permission to create TaskRuns or PipelineRuns that reference the HTTP resolver can point it at an attacker-controlled HTTP server that returns a very large response body within the 1-minute timeout window, causing the tekton-pipelines-resolvers pod to be OOM-killed by Kubernetes. Because all resolver types (Git, Hub, Bundle, Cluster, HTTP) run in the same pod, crashing this pod denies resolution service to the entire cluster. Repeated exploitation causes a sustained crash loop. The same vulnerable code path is reached by both the deprecated pkg/resolution/resolver/http and the current pkg/remoteresolution/resolver/http implementations. This vulnerability is fixed in 1.11.1.
Title Tekton Pipelines: HTTP Resolver Unbounded Response Body Read Enables Denial of Service via Memory Exhaustion
Weaknesses CWE-400
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Subscriptions

Tektoncd Pipeline
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-22T13:21:28.680Z

Reserved: 2026-04-15T20:40:15.517Z

Link: CVE-2026-40924

cve-icon Vulnrichment

Updated: 2026-04-22T13:21:13.460Z

cve-icon NVD

Status : Received

Published: 2026-04-21T21:16:45.720

Modified: 2026-04-22T14:17:02.833

Link: CVE-2026-40924

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-22T06:30:10Z

Weaknesses