CVE-2026-63087: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-whw8-2869-jf7j
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CVSS 9.8
CWE-306
Published
Advisory Summary

CVE-2026-63087 is a CRITICAL (CVSS 9.8) security vulnerability vulnerability (CWE-306: Missing Authentication for Critical Function) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-63087 at a Glance

CVE Identifier CVE-2026-63087
GHSA Identifier GHSA-whw8-2869-jf7j
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-306: Missing Authentication for Critical Function
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-63087

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-63087, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-306: Missing Authentication for Critical Function, where the product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Grafana OnCall through 1.16.11 contains an unauthenticated access vulnerability that allows remote attackers to obtain a valid PluginAuthToken by sending a POST request to the internal plugin install endpoint using hardcoded default stack_id and org_id values present in the public source tree. Attackers can leverage the acquired token to authenticate against all internal API endpoints, create arbitrary Admin users via the user-context header bootstrap path, revoke the legitimate plugin token, and redirect OnCall-to-Grafana API calls to an attacker-controlled host by overwriting the organization's grafana_url and api_token.

References

NVD — CVE-2026-63087 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-63087
Software Source Repository REPOSITORY
https://github.com/geo-chen/oss/blob/main/oncall.md
www.vulncheck.com/advisories/grafana-... WEB
https://www.vulncheck.com/advisories/grafana-oncall-unauthenticated-token-hijack-via-plugin-install-endpoint

Frequently Asked Questions

What is CVE-2026-63087?
CVE-2026-63087 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-306: Missing Authentication for Critical Function.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-63087?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-63087?
CVE-2026-63087 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-63087?
CVE-2026-63087 is classified under CWE-306: Missing Authentication for Critical Function (The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.).
How can I check Maven dependencies for CVE-2026-63087?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-whw8-2869-jf7j",
  "modified" : "2026-07-16T18:31:34Z",
  "published" : "2026-07-16T18:31:34Z",
  "aliases" : [ "CVE-2026-63087" ],
  "details" : "Grafana OnCall through 1.16.11 contains an unauthenticated access vulnerability that allows remote attackers to obtain a valid PluginAuthToken by sending a POST request to the internal plugin install endpoint using hardcoded default stack_id and org_id values present in the public source tree. Attackers can leverage the acquired token to authenticate against all internal API endpoints, create arbitrary Admin users via the user-context header bootstrap path, revoke the legitimate plugin token, and redirect OnCall-to-Grafana API calls to an attacker-controlled host by overwriting the organization's grafana_url and api_token.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-63087"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/geo-chen/oss/blob/main/oncall.md"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/grafana-oncall-unauthenticated-token-hijack-via-plugin-install-endpoint"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-306" ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-07-16T17:16:58Z"
  }
}