CVE-2026-18703: Improper Enforcement of Authentication Mechanism Restrictions in MongoDB Server Allows Use of Disabled Authentication Method
Noroxi assessment
Priority: Monitor (action score 9/100)
- 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: 0.14% (FIRST EPSS).
- Anyone who can reach it over the internet 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 8.3.8.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to MongoDB MongoDB Server 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 a party with a valid client certificate and a corresponding user account to authenticate using a certificate-based authentication method, even when an administrator has configured the server to restrict authentication to other mechanisms. This could allow authentication through a method the administrator intended to disable.
- Published
- Aug 11, 2026
- Updated
- Oct 23, 2026
- EPSS
- 0.1% · 3th percentile
- CWE
- CWE-863
Report tools
Action score
9
Monitor
Low priority for now.
- CVSS
- 9 / 40 · 2.3 / 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
- 2.3
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/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.
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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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| mongodb | mongodb | cpe:2.3:a:mongodb:mongodb |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- 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
Same product
mongodb: all recordsOther highest-scoring records for the same primary product.
- CVE-2025-14847Zlib compressed protocol header length confusion may allow memory readKEV89Now
- 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 r40Plan
- CVE-2025-3085MongoDB Server running on Linux may allow unexpected connections where intermediate certificates are revoked39Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-18701Aug 11, 2026 · Type Confusion in MongoDB Query Subsystem Leads to Denial of Service28Monitor
- ← EarlierCVE-2026-18702Aug 11, 2026 · Improper Authorization in MongoDB profile Command Allows Unauthorized Modification of Server-Wide Diagnostic Settings21Monitor
- Later →CVE-2026-18704Aug 11, 2026 · Improper Authorization in MongoDB Aggregation Framework Allows Read-Only User to Perform Unauthorized Write Operations28Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| MongoDB MongoDB Server | 8.3.8 | Vendor (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.
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 researchersFinders, 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-2026-8205328 days apartImproper Session Handling in MongoDB Server LDAP Authorization Integration Leads to Incorrect Role Assignment30Monitor
- CVE-2026-186900 days apartImproper Authorization in MongoDB Server Allows Unauthorized Actions on System Collections28Monitor
- CVE-2026-186960 days apartImproper Authorization in MongoDB applyOps Command Handling Allows Unauthorized DDL Operations on Collections28Monitor
- CVE-2026-187120 days apartImproper Authorization in MongoDB Queryable Encryption Maintenance Operations Allows Unauthorized Modification of Other Collections28Monitor
- CVE-2026-1306020 days apart$graphLookup Aggregation Stage Authorization Check Inconsistency Allowing Unauthorized Collection Access28Monitor
- CVE-2026-1306720 days aparttlsCATrusts Role Restriction Not Enforced via PROXY Protocol v2 on Unix Domain Socket28Monitor
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.
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0812 · Aug 12, 2026(MongoDB Güvenlik Bildirimi)
Technical details
Attack conditions
- Anyone who can reach it over the internet 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
- Network
- Attack complexity
- High
- Privileges required
- Low
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-863 · Incorrect AuthorizationCVSS vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/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.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.