CVE-2026-76236 stigmem before 0.9.0a12 Cross-Tenant BOLA via Tombstones
Cross-tenant BOLA in stigmem-node allows attackers to hide or expose data across tenants via flawed tombstone mechanisms in multi-tenant deployments.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-76236?
CVE-2026-76236 is a high-severity missing authorization vulnerability in eidetic-labs stigmem-node, published on 19 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
stigmem-node before 0.9.0a12 contains a cross-tenant broken object level authorization (BOLA) flaw in the RTBF (right-to-be-forgotten) tombstone mechanism. issue_tombstone defaulted the tenant to "default" instead of the caller's tenant, allowing deletion records to be written to the wrong tenant, and the read-suppression path (_get_tombstone_filter and the tombstone scope cache) lacked a tenant_id predicate, so tombstone suppression was applied tenant-blind across fact queries and provenance reads. As a result, a tenant's deletion could be attributed to the wrong tenant and tombstone suppression could either hide facts belonging to other tenants or fail to hide facts within the correct tenant, undermining data isolation and RTBF guarantees. The issue is exploitable only on multi-tenant deployments running the opt-in stigmem-plugin-multi-tenant; single-tenant deployments are unaffected. Fixed in 0.9.0a12.
Weakness: CWE-639
Which versions are affected by CVE-2026-76236?
2 open source packages ship an affected version, including stigmem-node.
| Package | Affected | Fixed in |
|---|---|---|
stigmem-node PyPI | All versions | 0.9.0a12 |
stigmem-node PyPI | All versions | 0.9.0a12 |
How do I fix CVE-2026-76236?
Upgrade stigmem-node to 0.9.0a12 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-76236 being exploited?
There is no known exploitation of CVE-2026-76236 in the wild and no public exploit code.
Sources
Also known as GHSA-77m3-9g4f-372v, GHSA-x26h-xmv8-gxf7.