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NVD / CVE Program· CNA mongodb

CVE-2026-18709: Missing Authorization in MongoDB Sharded Transaction Commit/Abort Handling Leads to Cross-Shard Data Inconsistency

Noroxi assessment

Priority: Monitor (action score 23/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
  • Someone on the same network segment can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: MongoDB MongoDB Server 7.0.40, 8.0.29, 8.3.8.

Low priority for now. Upgrade to MongoDB MongoDB Server 7.0.40, 8.0.29, 8.3.8 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.

MediumCVSS 5.9 · v4.0—No exploit Fix available
Published
Aug 11, 2026
Updated
Oct 23, 2026
EPSS
0.1% · 9th percentile

Report tools

JSON

Action score

23

Monitor

Low priority for now.

CVSS
23 / 40 · 5.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · mongodb
5.9
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-18709

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
mongodbmongodb

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • mongodb mongodb7.0.0 and later · before 7.0.40
  • mongodb mongodb8.0.0 and later · before 8.0.29
  • mongodb mongodb8.2.0 and later · up to 8.2.12 inclusive
  • mongodb mongodb8.3.0 and later · before 8.3.8
  • mongodb mongodb9.0.0
  • mongodb mongodb9.1.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (mongodb). Independent of NVD's CPE analysis and usually ahead of it.

  • MongoDB MongoDB Server

    • 8.3.0 and later · before 8.3.8affected · semver
    • 8.0 and later · before 8.0.29affected · semver
    • 7.0 and later · before 7.0.40affected · semver

Same product

mongodb: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-14847Zlib compressed protocol header length confusion may allow memory readKEV
    89Now
  • CVE-2013-1892MongoDB before 2.0.9 and 2.2.x before 2.2.4 does not properly validate requests to the nativeHelper function in SpiderMonkey, which allows r
    40Plan
  • CVE-2025-3085MongoDB Server running on Linux may allow unexpected connections where intermediate certificates are revoked
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-18705Aug 11, 2026 · Improper Authorization in MongoDB Atlas Vector Search Allows Unauthorized Access to Protected View Data
    28Monitor
  • ← EarlierCVE-2026-18706Aug 11, 2026 · Use-After-Free in MongoDB $graphLookup Aggregation Stage Leads to Denial of Service and Potential Remote Code Execution
    30Monitor
  • Later →CVE-2026-84967Sep 3, 2026 · Arbitrary command execution via shell-expanded connection string in Launch MongoDB Shell terminal
    20Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
MongoDB MongoDB Server7.0.40Vendor (CNA)
MongoDB MongoDB Server8.0.29Vendor (CNA)
MongoDB MongoDB Server8.3.8Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-187040 days apartImproper Authorization in MongoDB Aggregation Framework Allows Read-Only User to Perform Unauthorized Write Operations
    28Monitor
  • CVE-2026-1307820 days apartLocal File Disclosure in MongoDB Server via MozJS Scripting Engine Module Loader
    25Monitor
  • CVE-2026-25609182 days apartprofile command may permit unauthorized configuration
    21Monitor
  • CVE-2025-13643259 days apartMongoDB Server may allow queries to be terminated by unauthorized users
    9Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

Technical details

Attack conditions

  • Someone on the same network segment can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
Integrity
Availability
Attack vector
Adjacent
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
X

Weakness class (CWE)

CWE-862 · Missing Authorization

CVSS vector

CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records