CVE-2026-46668: SpiceDB Caveat Structures With Nested Lists Vulnerability

LOW
Advisory Identifier: GHSA-mqcf-gqvg-rmhm
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CWE-285
Published
Advisory Summary

CVE-2026-46668 is a LOW caveat structures with nested lists vulnerability (CWE-285: Improper Authorization) affecting SpiceDB libraries in the Go ecosystem. The issue involves caveat structures with nested lists can result in improper cache reuse. Remediation is available by upgrading affected packages to version 1.52.0.

CVE-2026-46668 at a Glance

CVE Identifier CVE-2026-46668
GHSA Identifier GHSA-mqcf-gqvg-rmhm
Severity LOW
CVSS v3.1 Base Score N/A
CWE Classification CWE-285: Improper Authorization
Affected Product SpiceDB
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-46668

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

github.com/authzed/spicedb fixed: 1.52.0 
Upgrade github.com/authzed/spicedb to 1.52.0
Verify Direct and Transitive Dependencies

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

inspect dependencies for github.com/authzed/spicedb

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-46668, inspect your project dependencies for SpiceDB:

inspect dependencies for github.com/authzed/spicedb

Analyze the terminal output to locate any version of SpiceDB in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.52.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-285: Improper Authorization, where the product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. In SpiceDB, 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

### Impact Users are impacted if: - They have a caveat structure with a nested list, e.g.: ```zed caveat shape(x list<any>) { x == [["a"], "b"] } ``` - Their system exercises that caveat with either [CheckBulkPermission](https://buf.build/authzed/api/docs/main%3Aauthzed.api.v1#authzed.api.v1.PermissionsService.CheckBulkPermissions) or else [LookupResources](https://buf.build/authzed/api/docs/main%3Aauthzed.api.v1#authzed.api.v1.PermissionsService.LookupResources) running with the `--experimental-lookup-resources-version` flag set to `lr3`, implying they are using the experimental version 3 of `LookupResources` - An attacker can cause the system to craft a request to SpiceDB where either: 1. It's a `CheckBulk` request where there are two check items that are identical except for their combined caveat context, and one of the caveat contexts evaluates positively and the other evaluates negatively 2. It's a `LookupResources` request where two resources have the same evaluation contents except for their caveat context, and one would evaluate positively and the other would evaluate negatively If all of the above are true, it would be possible for SpiceDB to erroneously return that a user has access to a resource that they do not have access to. ### Patches This problem was addressed in https://github.com/authzed/spicedb/pull/3065 and released in version v1.52.0. ### Workarounds If using v3 of `LookupResources`, turn the flag off. If possible, refactor the `caveat` declaration structure so that it does not operate on a list of lists, but rather any other composite structure.

CVE-2026-46668 Affected SpiceDB Versions

1 component(s)
Fixed Versions:
1.52.0
Product / Package Ecosystem Affected Versions Fixed Version
github.com/authzed/spicedb
golang/github.com/authzed/spicedb
Go
≥ 1.15.0
< 1.52.0
1.52.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/authzed/spicedb/security/advisories/GHSA-mqcf-gqvg-rmhm
NVD — CVE-2026-46668 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-46668
SpiceDB Source Repository REPOSITORY
https://github.com/authzed/spicedb/pull/3065
SpiceDB Source Repository REPOSITORY
https://github.com/authzed/spicedb
SpiceDB Release RELEASE
https://github.com/authzed/spicedb/releases/tag/v1.52.0

Frequently Asked Questions

What is CVE-2026-46668?
CVE-2026-46668 is a security vulnerability in SpiceDB involving Caveat structures with nested lists can result in improper cache reuse under CWE-285: Improper Authorization.
Which SpiceDB versions are affected?
Affected versions include releases prior to 1.52.0 across affected packages: github.com/authzed/spicedb.
What version fixes CVE-2026-46668?
Upgrading to 1.52.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/authzed/spicedb affected?
Yes, github.com/authzed/spicedb is affected in releases prior to 1.52.0. Upgrade your dependency to 1.52.0 or later.
What CWE is associated with CVE-2026-46668?
CVE-2026-46668 is classified under CWE-285: Improper Authorization (The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.).
How can I check Go dependencies for CVE-2026-46668?
Run the dependency tree command: 'inspect dependencies for github.com/authzed/spicedb'. 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-mqcf-gqvg-rmhm",
  "modified" : "2026-06-11T14:05:32Z",
  "published" : "2026-05-21T20:28:43Z",
  "aliases" : [ "CVE-2026-46668" ],
  "summary" : "SpiceDB: Caveat structures with nested lists can result in improper cache reuse",
  "details" : "### Impact\nUsers are impacted if:\n\n- They have a caveat structure with a nested list, e.g.:\n  \n```zed\n  caveat shape(x list<any>) {\n    x == [[\"a\"], \"b\"]\n  }\n  ```\n- Their system exercises that caveat with either [CheckBulkPermission](https://buf.build/authzed/api/docs/main%3Aauthzed.api.v1#authzed.api.v1.PermissionsService.CheckBulkPermissions) or else [LookupResources](https://buf.build/authzed/api/docs/main%3Aauthzed.api.v1#authzed.api.v1.PermissionsService.LookupResources) running with the `--experimental-lookup-resources-version` flag set to `lr3`, implying they are using the experimental version 3 of `LookupResources`\n-  An attacker can cause the system to craft a request to SpiceDB where either:\n    1. It's a `CheckBulk` request where there are two check items that are identical except for their combined caveat context, and one of the caveat contexts evaluates positively and the other evaluates negatively\n    2. It's a `LookupResources` request where two resources have the same evaluation contents except for their caveat context, and one would evaluate positively and the other would evaluate negatively\n\nIf all of the above are true, it would be possible for SpiceDB to erroneously return that a user has access to a resource that they do not have access to.\n\n### Patches\nThis problem was addressed in https://github.com/authzed/spicedb/pull/3065 and released in version v1.52.0.\n\n### Workarounds\nIf using v3 of `LookupResources`, turn the flag off.\n\nIf possible, refactor the `caveat` declaration structure so that it does not operate on a list of lists, but rather any other composite structure.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/authzed/spicedb"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.15.0"
      }, {
        "fixed" : "1.52.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/authzed/spicedb/security/advisories/GHSA-mqcf-gqvg-rmhm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-46668"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/authzed/spicedb/pull/3065"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/authzed/spicedb"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/authzed/spicedb/releases/tag/v1.52.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-285" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-21T20:28:43Z",
    "nvd_published_at" : "2026-06-10T22:16:59Z"
  }
}