CVE-2026-1709: Keylime Keylime Missing Authentication For Critical Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-4jqp-9qjv-57m2",
  "modified" : "2026-06-06T00:37:09Z",
  "published" : "2026-02-06T22:34:44Z",
  "aliases" : [ "CVE-2026-1709" ],
  "summary" : "Keylime Missing Authentication for Critical Function and Improper Authentication",
  "details" : "### Impact\n\nThe Keylime registrar does not enforce mutual TLS (mTLS) client certificate authentication since version 7.12.0. The registrar's TLS context is configured with `ssl.CERT_OPTIONAL` instead of `ssl.CERT_REQUIRED`, allowing any client to connect to protected API endpoints without presenting a valid client certificate.\n\n**Who is impacted:**\n  - All Keylime deployments running versions 7.12.0 through 7.13.0\n  - Environments where the registrar HTTPS port (default 8891) is network-accessible to untrusted clients\n\n**What an attacker can do:**\n  - **List all registered agents** (`GET /v2/agents/`) - enumerate the entire agent inventory\n  - **Retrieve agent details** (`GET /v2/agents/{uuid}`) - obtain public TPM keys, certificates, and network locations (IP/port) of any agent\n  - **Delete any agent** (`DELETE /v2/agents/{uuid}`) - remove agents from the registry, disrupting attestation services\n\nNote: The exposed TPM data (EK, AK, certificates) consists of public keys and certificates. Private keys remain protected within TPM hardware. The HMAC secret used for challenge-response validation is stored in the database but is not exposed via the API.\n\n**Affected versions:** >= 7.12.0, <= 7.13.0\n\n**Fixed versions:** 7.12.2, >= 7.13.1\n\n### Patches\n\nA patch for the affected released versions is available. It removes the line that override the configuration of `ssl.verify_mode`, leaving the `CERT_REQUIRED` value set by `web_util.init_mtls()`:\n\n```diff\ndiff --git a/keylime/web/base/server.py b/keylime/web/base/server.py\nindex 1d9a9c2..859b23a 100644\n--- a/keylime/web/base/server.py\n+++ b/keylime/web/base/server.py\n@@ -2,7 +2,6 @@ import asyncio\n import multiprocessing\n from abc import ABC, abstractmethod\n from functools import wraps\n-from ssl import CERT_OPTIONAL\n from typing import TYPE_CHECKING, Any, Callable, Optional\n\n import tornado\n@@ -252,7 +251,6 @@ class Server(ABC):\n         self._https_port = config.getint(component, \"tls_port\", fallback=0)\n         self._max_upload_size = config.getint(component, \"max_upload_size\", fallback=104857600)\n         self._ssl_ctx = web_util.init_mtls(component)\n-        self._ssl_ctx.verify_mode = CERT_OPTIONAL\n\n     def _get(self, pattern: str, controller: type[\"Controller\"], action: str, allow_insecure: bool = False) -> None:\n         \"\"\"Creates a new route to handle incoming GET requests issued for paths which match the given\n```\n\nUsers should upgrade to the patched version once it is released.\n\n### Workarounds\n\nIf upgrading is not immediately possible, apply one of the following mitigations:\n\n#### 1. Network isolation (Recommended)\n\nRestrict access to the registrar HTTPS port (default 8891) using firewall rules\nto allow only trusted hosts (verifier, tenant):\n\n##### Example using iptables\n```\niptables -A INPUT -p tcp --dport 8891 -s <verifier_ip> -j ACCEPT\niptables -A INPUT -p tcp --dport 8891 -s <tenant_ip> -j ACCEPT\niptables -A INPUT -p tcp --dport 8891 -j DROP\n```\n\n#### 2. Reverse proxy with mTLS enforcement\n\nDeploy a reverse proxy (nginx, HAProxy) in front of the registrar that enforces client certificate authentication:\n\n##### Example nginx configuration\n```\nserver {\n    listen 8891 ssl;\n    ssl_certificate /path/to/server.crt;\n    ssl_certificate_key /path/to/server.key;\n    ssl_client_certificate /path/to/ca.crt;\n    ssl_verify_client on;  # Enforce client certificates\n\n    location / {\n        proxy_pass https://localhost:8892;  # Internal registrar port\n    }\n}\n```",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "keylime"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "7.12.0"
      }, {
        "fixed" : "7.12.2"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "keylime"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "7.13.0"
      }, {
        "fixed" : "7.13.1"
      } ]
    } ],
    "versions" : [ "7.13.0" ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/keylime/keylime/security/advisories/GHSA-4jqp-9qjv-57m2"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-1709"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:2224"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:2225"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:2298"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/security/cve/CVE-2026-1709"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2435514"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/keylime/keylime"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/keylime/PYSEC-2026-74.yaml"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-295", "CWE-306" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-06T22:34:44Z",
    "nvd_published_at" : null
  }
}