CVE-2026-9740
Unbounded recursion in BSONColumn interleaved-reference causes pre-auth stack overflow
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Unbounded recursion in BSONColumn interleaved-reference causes pre-auth stack overflow
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.
- Record
CVE-2026-9740- CVSS 4.0
- 8.7 High
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 - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
EUVDEUVD-2026-35857
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.
- Record
EUVD-2026-35857- CVSS 4.0
- 8.7 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-wvrr-4w4f-3v54
A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash...
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.
- Record
GHSA-wvrr-4w4f-3v54- CVSS 4.0
- 8.7 High
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 - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-9740- CVSS 4.0
- 8.7 High
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 - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
OSV
Unbounded recursion in BSONColumn interleaved-reference causes pre-auth stack overflow
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.
- Record
CVE-2026-9740- CVSS 4.0
- 8.7 High
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 - Weakness
- CWE-674
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-9740
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.
- Record
UBUNTU-CVE-2026-9740- CVSS 4.0
- 8.7 High
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 - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVBIT-mongodb-2026-9740 No score
Unbounded recursion in BSONColumn interleaved-reference causes pre-auth stack overflow
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.
- Record
BIT-mongodb-2026-9740- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mongodbBitnami |
7.0.0 up to 7.0.35, 8.0.0 up to 8.0.24, 8.2.0 up to 8.2.10, 8.3.0 up to 8.3.3 | 7.0.358.0.248.2.108.3.3 |
mongodbUbuntu:Pro:14.04:LTS |
All versions, plus listed versions 1:2.4.6-0ubuntu51:2.4.6-0ubuntu61:2.4.8-1ubuntu11:2.4.8-21:2.4.9-11:2.4.9-1ubuntu11:2.4.9-1ubuntu21:2.4.9-1ubuntu2+esm2 |
None known |
mongodbUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 1:2.6.10-0ubuntu11:2.6.10-0ubuntu1+esm2 |
None known |
mongodbUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 1:3.4.7-11:3.4.7-1ubuntu11:3.4.7-1ubuntu21:3.4.7-1ubuntu41:3.4.14-3ubuntu1 Show 7 moreShow less1:3.4.14-3ubuntu21:3.6.3-0ubuntu11:3.6.3-0ubuntu1.11:3.6.3-0ubuntu1.31:3.6.3-0ubuntu1.41:3.6.3-0ubuntu1.4+esm11:3.6.3-0ubuntu1.4+esm2 |
None known |
mongodbUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu21:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu51:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.21:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.31:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.3+esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-9740 is a high vulnerability (CVSS 8.7) in Mongodb, published June 9, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.34%, the 28th percentile. Fixed in mongodb 7.0.35.