CVE-2026-9740

highpriority · track · 0EPSS 0.003 · 28 %ileDEEUNLRUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.34% (28th) EPSS
CVSS 7.5 · high
Is it mine?
29 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash the mongod process by sending a specially crafted message. The BSON validator's handling of certain nested binary data structures permits uncontrolled mutual recursion between validation functions, where each re-entry resets internal depth tracking.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.7
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · cna@mongodb.comexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL
v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU
v4.08.7highCVSS: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:Xsecondary · cna@mongodb.com
v4.06.6mediumCVSS: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:U/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:Xsecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-674USCWE-674USCWE-674US
03

affected products (29)

Products and version ranges known to be affected.

showing 20 of 29
04

advisories (3)

Vendor and ecosystem advisories describing this.

  • NCSC-2026-0209Kwetsbaarheden verholpen in MongoDB ServerNL2026-06-23csaf · ncsc_nlNL

    MongoDB heeft meerdere kwetsbaarheden verholpen in MongoDB Server.

  • WID-SEC-W-2026-1868MongoDB: Mehrere SchwachstellenDeutsch2026-06-09csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in MongoDB ausnutzen, um einen Denial of Service Angriff durchzuführen oder vertrauliche Informationen offenzulegen.

  • BIT-mongodb-2026-9740Unbounded recursion in BSONColumn interleaved-reference causes pre-auth stack overflow2026-06-16vendor · osvUS

    A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash the mongod process by sending a specially crafted message. The BSON validator's handling of certain nested binary data structures permits uncontrolled mutual recursion between validation functions, where each re-entry resets internal depth tracking.

05

also known as (5)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundncsc_nlosvNVDCVE.orgMITRE
published 2026-06-09modified 2026-09-25
07

references (4)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan