What is CVE-2026-93759?

CVE-2026-93759 is Server-side JavaScript injection via string query criteria bypassing the strict operator allowlist. The supplied enrichment data classifies it as Remote Code Exec mapped to CWE-94 Code Injection.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Active exploitation is not confirmed from current sources for CVE-2026-93759. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

No. CVE-2026-93759 is not listed in CISA KEV in the supplied enrichment data. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Is there a public exploit?

A public PoC is not confirmed from current sources for CVE-2026-93759. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with web/proxy/WAF logs, application logs, network IDS/IPS, EDR process telemetry, host service logs where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2026-93759 using CVSS 8.6, EPSS 0%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

No public threat actor linkage is confirmed from current sources. Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Prioritize based on EPSS, PoC availability, and external exposure. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

highRemote Code Exec

CVE-2026-93759

CVE-2026-93759 — Server-side JavaScript injection via string query criteria bypassing the strict operator allowlist

Mongoid does not neutralize a string-typed query criterion supplied to its query builder, and instead passes it to the database as a server-side JavaScript expression. An unauthenticated party able to influence the value an application supplies as a query argument may cause code of their choosing to be evaluated by the database engine. This may result in unintended disclosure of stored field values, unintended selection of documents for application-initiated writes, and reduced database performance.

Published Sep 18, 2026Updated Sep 24, 2026Sources: NVD, MongoDB Inc. (CNA), GitHub, Red Hat (VEX)

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

chance of exploitation in 30 days

Affects

MongoDB Inc.

4 products listed

CVSS base

8.6

high · 2 sources

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

Yes

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

Upgrade Mongoid to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

Red Hat VEX · CVE-2026-93759

fixed0affected0not affected1

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Prioritize based on EPSS, PoC availability, and external exposure.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
MongoDB Inc.	Mongoid	9.1.0	Vulnerable
MongoDB Inc.	Mongoid	9.0.0 to <= 9.0.11	Vulnerable
MongoDB Inc.	Mongoid	8.1.0 to <= 8.1.12	Vulnerable
MongoDB Inc.	Mongoid	8.0.0 to <= 8.0.12	Vulnerable

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Availability

Low

Confidentiality

High

Integrity

Low

Scope

Unchanged

Attack Complexity

Low

Attack Vector

Network

Privileges Req

None

User Interaction

None

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
8.6	CVSS 3.1	high	3.9	4.7	mongodb.com (CNA), MongoDB Inc. (CNA), Red Hat (VEX)
8.8	CVSS 4.0	high	—	—	MongoDB Inc. (CNA)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L

Weakness & attack patterns

CWE-94Code Injection

Inferred from the weakness class — not observed against this CVE.

CAPEC-242 · Code InjectionCAPEC-35 · Leverage Executable Code in Non-Executable Files

T1027.006Obfuscated Files or Information: HTML Smuggling
T1027.009Obfuscated Files or Information: Embedded Payloads
T1564.009Hide Artifacts: Resource Forking

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Prioritize edge telemetry for network-reachable Mongoid.

web/proxy/WAF logsapplication logsnetwork IDS/IPSEDR process telemetryhost service logs

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added · CVSS 3.1 8.6 (AV:N)
Sep 24, 2026 · NVD
Initial · CVE published
Sep 18, 2026 · NVD

References

3 on the record

jira.mongodb.org/browse/MONGOID-5993
Permissions Required
access.redhat.com/security/cve/CVE-2026-93759
Vendor Advisory
www.cve.org/CVERecord?id=CVE-2026-93759
Vendor Advisory

Elsewhere on this site

MongoDB Inc.every CVE for this vendor
Remote Code Execsame class
CWE-94other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record1

What should defenders know first?

CVE-2026-93759 is Server-side JavaScript injection via string query criteria bypassing the strict operator allowlist, a high vulnerability affecting Mongoid from MongoDB Inc.. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-93759. Public exploit evidence is: A public PoC is not confirmed from current sources for CVE-2026-93759. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.6 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.