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NVD / CVE Program· CNA mongodb

CVE-2026-93761: Denial of service via unbounded regex matching in Mongoid's in-memory query matcher

HighCVSS 8.7 · v4.0—No exploit No fix recorded

Noroxi assessment

Priority: Monitor (action score 34/100)

  • 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: 0.46% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • According to the record, no fixed version is available yet.

Low priority for now. Update when a fix is released; follow the vendor's advisory.

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 inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.

Published
Sep 18, 2026
Updated
Sep 24, 2026
EPSS
0.4% · 40th percentile

Report tools

JSON

Action score

34

Monitor

Low priority for now.

CVSS
34 / 40 · 8.7 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · mongodb
8.7
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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
  • No fixed version yet

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

Follow CVE-2026-93761

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
mongodbmongoid

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 Inc. Mongoid

    • 9.1.0affected
    • 7.2.0 and later · up to and including 7.2.6affected · semver
    • 7.3.0 and later · up to and including 7.3.5affected · semver
    • 7.4.0 and later · up to and including 7.4.3affected · semver
    • 7.5.0 and later · up to and including 7.5.4affected · semver
    • 7.6.0 and later · up to and including 7.6.1affected · semver
    • 8.0.0 and later · up to and including 8.0.12affected · semver
    • 8.1.0 and later · up to and including 8.1.12affected · semver
    • 9.0.0 and later · up to and including 9.0.11affected · semver
Affected versions · NVD (4)

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

  • mongodb mongoid8.0.0 and later · before 8.0.13
  • mongodb mongoid8.1.0 and later · before 8.1.13
  • mongodb mongoid9.0.0 and later · before 9.0.12
  • mongodb mongoid9.1.0

Same product

mongodb: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-93762Data deletion and attribute disclosure via field-name method injection in in-memory queries
    36Monitor
  • CVE-2026-93759Server-side JavaScript injection via string query criteria bypassing the strict operator allowlist
    35Monitor
  • CVE-2026-93758Cross-principal document update, theft, and deletion via unvalidated id in nested attributes
    34Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-93765Sep 18, 2026 · Document deletion and process crash via unvalidated method-name dispatch in atomic pop operation
    33Monitor
  • ← EarlierCVE-2026-93760Sep 18, 2026 · NoSQL injection of JavaScript-executing query operators via unsafe-by-default operator guard
    33Monitor
  • Later →CVE-2026-93763Sep 18, 2026 · Silent plaintext persistence via unresolved callable database name in encryption schema map
    28Monitor

Remediation

Which version to upgrade to

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

No fix version is recorded for this entry. Check the references for vendor advisories.

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).

Bug bounty scope

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

Not on record for this CVE: patch commit or PR link · researcher credit · variant or chain candidate.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

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

Weakness class (CWE)

CWE-1333 · Inefficient Regular Expression Complexity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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.

ATT&CK techniques

—

References

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

All records