MongoDBDatabase / datastore
CVE-2026-5170
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA user with access to the cluster with a limited set of privilege actions can trigger a crash of a mongod process during the limited and unpredictable window when the cluster is being promoted from a replica set to a sharded cluster. This may cause a denial of service by taking down the primary of the replica set. This issue affects MongoDB Server v8.2 versions prior to 8.2.2, MongoDB Server v8.0 versions between 8.0.18, MongoDB Server v7.0 versions between 7.0.31.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysisAttacker-controllable input can reach an assertion that aborts the process when it fails, so a check meant for debugging becomes a denial-of-service in production. A single crafted request takes the service down. The fix is to handle unexpected input gracefully on reachable paths rather than asserting on it.
General guidance for the reachable assertion class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
MongoDBDatabase / datastore
>= 7.0.0, < 7.0.31>= 8.0.0, < 8.0.18>= 8.2.0, < 8.2.2CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- High
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped7.0.318.0.188.2.2
7.0.31 (for 7.0.x) or 8.0.18 (for 8.0.x) or 8.2.2 (for 8.2.x)
- Identify your current MongoDB Server version using db.version() or mongod --version
- Determine which upgrade path applies: 7.0.x -> 7.0.31, 8.0.x -> 8.0.18, or 8.2.x -> 8.2.2
- Back up all databases following MongoDB backup best practices
- Test the upgrade in a non-production environment first
- Stop the mongod process gracefully before upgrading
- Upgrade MongoDB Server to the appropriate fixed version (7.0.31, 8.0.18, or 8.2.2)
- Start the mongod process and verify successful startup
- Verify cluster functionality and confirm the fix by testing replica set to sharded cluster promotion
Generated from the published advisory — verify against the referenced sources before acting.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-5170 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-5170 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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