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

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.3 · CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

EPSS

• CVE-2026-116575: 0.11% estimated exploitation activity in the next 30 days; percentile 1.19 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary _build_session_scope() in mem0/memory/main.py builds the conversation-history scope key used to fetch/store the last N raw messages by naively joining caller-supplied user_id/agent_id/run_id values with unescaped & and = delimiters: def _build_session_scope(filters): parts = [] for key in sorted(["user_id", "agent_id", "run_id"]): val = filters.get(key) if val: parts.append(f"{key}={val}") return "&".join(parts) _validate_and_trim_entity_id() (the only validation applied to these values) rejects only empty/whitespace-only strings — it never forbids & or =. This scope string is then used as an exact-match key against a SQLite column (storage.py: WHERE session_scope = ?) to fetch the last 10 raw messages for a given scope (main.py, Phase 0 of _add_to_vector_store, both sync and async). Impact Any caller who controls only their own run_id (or agent_id) — a very common integration shape, since apps frequently pass a client-/session-supplied identifier straight through as run_id…

Published by the source

28 Oct 2026, 21:17 UTC

Last modified by the source

28 Oct 2026, 21:30 UTC

Source last checked

29 Oct 2026, 06:00 UTC

1. Revision 2 · amended · 29 Oct 2026

   Amended from osv record GHSA-5324-3w58-qpp2

2. Revision 1 · created · 28 Oct 2026

   Published from ghsa record GHSA-5324-3w58-qpp2

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# Patch Next advisory brief: CVE-2026-116575

Advisory: Mem0: Cross-tenant conversation leak via unescaped delimiter collision in session-scope key (_build_session_scope)
IDs: CVE-2026-116575, GHSA-5324-3w58-qpp2
Record: https://patchnext.com/advisories/cve-2026-116575 (revision 2, source checked 29 Oct 2026, 06:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: mem0ai 2.0.18; mem0ai 3.1.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI mem0ai: affected < 2.0.18; fixed in 2.0.18
- npm mem0ai: affected < 3.1.6; fixed in 3.1.6

## Suggested inspection (read-only)
- `python -m pip show mem0ai`: prints the installed version. Run with the environment that serves production active.
- `npm ls mem0ai --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on mem0ai.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-5324-3w58-qpp2 (OSV record GHSA-5324-3w58-qpp2 lists affected ranges: PyPI mem0ai >=0 =0 <3.1.6 (fixed))
- Verified: https://github.com/advisories/GHSA-5324-3w58-qpp2 (GitHub-reviewed advisory GHSA-5324-3w58-qpp2 lists affected ranges: PyPI mem0ai >=0 =0 <3.1.6)

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