CVE-2026-76236

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/eidetic-labs/stigmem/security/advisories/GHSA-x26h-xmv8-gxf7
https://www.vulncheck.com/advisories/stigmem-before-0a12-cross-tenant-bola-via-tombstones

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 14:17

Updated : 2026-09-11 18:28

NVD link : CVE-2026-76236

Mitre link : CVE-2026-76236

CVE.ORG link : CVE-2026-76236

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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