CVE-2026-18709
Missing Authorization in MongoDB Sharded Transaction Commit/Abort Handling Leads to Cross-Shard Data Inconsistency
CVE-2026-18709 is a medium vulnerability (CVSS 5.9) in Mongodb, published August 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 9th percentile. Fixed in mongodb 7.0.40.
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Missing Authorization in MongoDB Sharded Transaction Commit/Abort Handling Leads to Cross-Shard Data Inconsistency
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
CVE-2026-18709- CVSS 4.0
- 5.9 Medium
CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-862
- Updated
- 2026-11-02
EUVDEUVD-2026-56883
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
EUVD-2026-56883- CVSS 4.0
- 5.9 Medium
CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-g2m8-vcxw-5h4c
An issue in MongoDB Server could allow an authenticated user with direct network access to a...
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
GHSA-g2m8-vcxw-5h4c- CVSS 4.0
- 5.9 Medium
CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/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
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-862
- Updated
- 2026-11-02
NVD
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
CVE-2026-18709- CVSS 4.0
- 5.9 Medium
CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/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
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-862
- Updated
- 2026-11-02
OSV
Missing Authorization in MongoDB Sharded Transaction Commit/Abort Handling Leads to Cross-Shard Data Inconsistency
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
CVE-2026-18709- CVSS 4.0
- 5.9 Medium
CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-18709
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
UBUNTU-CVE-2026-18709- CVSS 4.0
- 5.9 Medium
CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
OSVBIT-mongodb-2026-18709 No score
Missing Authorization in MongoDB Sharded Transaction Commit/Abort Handling Leads to Cross-Shard Data Inconsistency
An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.
- Record
BIT-mongodb-2026-18709- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mongodbBitnami |
7.0.0 up to 7.0.40, 8.0.0 up to 8.0.29, 8.2.0 up to 8.3.8, 9.0.0 up to 9.0.2 | 7.0.408.0.298.3.89.0.2 |
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
| When | Changed | Sources |
|---|---|---|
| 2026-11-02 | created | CVE List, EUVD, GitHub Advisories, NVD, OSV |