{"id":"GHSA-x26h-xmv8-gxf7","title":"stigmem-node: RTBF tombstones are mis-attributed and suppress reads tenant-blind (cross-tenant BOLA)","summary":"stigmem-node: RTBF tombstones are mis-attributed and suppress reads tenant-blind (cross-tenant BOLA)","severity":"high","cwe":["CWE-639"],"vendor":"stigmem-node","product":"stigmem-node","ecosystem":"pip","affected":["stigmem-node < 0.9.0a12"],"patched":["stigmem-node 0.9.0a12"],"published":"2026-06-19","updated":"2026-06-19","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-x26h-xmv8-gxf7","references":[{"url":"https://github.com/eidetic-labs/stigmem/security/advisories/GHSA-x26h-xmv8-gxf7"},{"url":"https://github.com/eidetic-labs/stigmem/pull/728"},{"url":"https://github.com/advisories/GHSA-x26h-xmv8-gxf7"}],"tags":["ghsa","pip"],"ingestedAt":"2026-06-22T13:35:24.238Z","slug":"GHSA-x26h-xmv8-gxf7","body":"## Overview\n\n### Summary\nOn a multi-tenant stigmem node, RTBF (right-to-be-forgotten) tombstones were mis-scoped two ways. (1) `issue_tombstone` defaulted the tenant to `\"default\"` instead of the caller's tenant, so tombstones could be written to the wrong tenant. (2) The read-suppression path — `_get_tombstone_filter` (`routes/facts/common.py`) and the `_tombstone_scope_cache` (`lifecycle/tombstones.py`) — had no `tenant_id` predicate, so tombstone suppression was applied tenant-blind across fact queries and provenance. Reached via `/v1/tombstones` and the fact query/provenance read paths.\n\n### Impact\nCross-tenant integrity of the RTBF mechanism: a tenant's deletion request could be recorded against the wrong tenant, and tombstone suppression could hide — or fail to hide — facts across tenant boundaries, undermining both data-view correctness and RTBF guarantees.\n\n### Affected configurations\nThis is a cross-**tenant** break. It is exploitable **only** on deployments running the opt-in `stigmem-plugin-multi-tenant` (multiple tenants on one node). A default single-tenant node has only `tenant=\"default\"` — there is no second tenant to cross — so it is **not exploitable** on default deployments. The rating is HIGH for the multi-tenant deployments the plugin exists to isolate.\n\n### Patches\nFixed in `0.9.0a12` (PR #728): `identity.tenant_id` is passed from `issue_tombstone` into `create_tombstone` (no more `\"default\"` fallback); `AND tenant_id = ?` was added to `_get_tombstone_filter` and `get_tombstone_status`; the suppression cache is re-keyed to include tenant; and all four read call sites thread the caller's tenant. A tenant-B tombstone now suppresses only tenant-B facts and is invisible to tenant-A reads.\n\n### Workarounds\nNone other than upgrading to `0.9.0a12`. Single-tenant deployments are unaffected.\n\n## Affected packages\n\n- `stigmem-node < 0.9.0a12`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `stigmem-node 0.9.0a12`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}