Mem0: Cross-tenant conversation leak via unescaped delimiter collision in session-scope key (_build_session_scope)

{
  "id": "3c8d1449eedc0b95a6ccc6abf32625e3c79b64ef3394f8970ed66d0df6363e4a",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-116575",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Mem0: Cross-tenant conversation leak via unescaped delimiter collision in session-scope key (_build_session_scope)",
    "summary": "Mem0 provides persistent memory infrastructure for AI agents and applications. Prior to Python SDK 2.0.18 and TypeScript SDK 3.1.6, _build_session_scope() in mem0/memory/main.py and Memory.buildSessionScope() in the TypeScript SDK join caller-controlled user_id, agent_id, and run_id values using unescaped & and = delimiters. A caller can embed another scope component in a controlled identifier so that distinct tenant tuples produce the same session_scope key. Memory.add(), AsyncMemory.add(), and the REST POST /memories flow use that key to read and save recent raw messages, allowing cross-tenant conversation disclosure and eviction or interleaving of another tenant's history. This issue is fixed in Python SDK 2.0.18 and TypeScript SDK 3.1.6.",
    "evidence": "cve:CVE-2026-116575",
    "products": [
      {
        "name": {
          "value": "mem0",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-116575",
      "aliases": [
        "CVE-2026-116575"
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "scope": "UNCHANGED",
            "version": "3.1",
            "baseScore": 6.3,
            "attackVector": "LOCAL",
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
            "integrityImpact": "HIGH",
            "userInteraction": "NONE",
            "attackComplexity": "HIGH",
            "availabilityImpact": "NONE",
            "privilegesRequired": "LOW",
            "confidentialityImpact": "HIGH"
          }
        }
      ],
      "affected": [
        {
          "vendor": "mem0ai",
          "product": "mem0",
          "versions": [
            {
              "status": "affected",
              "version": "< 2.0.18"
            }
          ]
        }
      ],
      "modified": "2026-10-27T14:18:25.039Z",
      "provider": "cve",
      "references": [
        "https://github.com/mem0ai/mem0/security/advisories/GHSA-5324-3w58-qpp2",
        "https://github.com/mem0ai/mem0/pull/6892",
        "https://github.com/mem0ai/mem0/commit/71f2ebefa3494da21550fb525216818776cde67f",
        "https://github.com/mem0ai/mem0/releases/tag/ts-v3.1.6",
        "https://github.com/mem0ai/mem0/releases/tag/v2.0.18"
      ],
      "provider_metadata": {
        "adp": [
          {
            "title": "CISA ADP Vulnrichment",
            "metrics": [
              {
                "other": {
                  "type": "ssvc",
                  "content": {
                    "id": "CVE-2026-116575",
                    "role": "CISA Coordinator",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "total"
                      }
                    ],
                    "version": "2.0.3",
                    "timestamp": "2026-10-27T13:45:14.377647Z"
                  }
                }
              }
            ],
            "providerMetadata": {
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP",
              "dateUpdated": "2026-10-27T14:18:25.039Z"
            }
          }
        ],
        "cna": {
          "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
          "shortName": "GitHub_M",
          "dateUpdated": "2026-10-26T20:15:01.875Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-116575",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/containers/cna/metrics"
  },
  "source_id": "core-cve",
  "document_id": 392641,
  "published_at": "2026-10-26T20:15:01.875+00:00"
}