CyberSecBulletin
CVE-2025-6706NVD status: Analyzed

MongoDB Server: Use After Free

CVE-2025-6706 is a high-severity use after free vulnerability in MongoDB Server from MongoDB, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 6.0.21, 7.0.17, 8.0.4 as the first without the flaw, so updating MongoDB Server to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.27% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update MongoDB Server to 6.0.21 or 7.0.17 or 8.0.4, whichever matches your release line, or a later version.
  2. Update Mongodb to 6.0.21 or 7.0.17 or 8.0.4, whichever matches your release line, or a later version.
  3. Read the advisory on jira.mongodb.org for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
MongoDBMongoDB Server6.0 up to, but not including, 6.0.21; 7.0 up to, but not including, 7.0.17; 8.0 up to, but not including, 8.0.46.0.21, 7.0.17, 8.0.4
MongoDBMongodb6.0.0 up to, but not including, 6.0.21; 7.0.0 up to, but not including, 7.0.17; 8.0.0 up to, but not including, 8.0.46.0.21, 7.0.17, 8.0.4

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.15.0MediumCNA (mongodb.com)
CVSS 3.18.8HighNVD

Official description

An authenticated user may trigger a use after free that may result in MongoDB Server crash and other unexpected behavior, even if the user does not have authorization to shut down a server. The crash is triggered on affected versions by issuing an aggregation framework operation using a specific combination of rarely-used aggregation pipeline expressions. This issue affects MongoDB Server v6.0 version prior to 6.0.21, MongoDB Server v7.0 version prior to 7.0.17 and MongoDB Server v8.0 version prior to 8.0.4 when the SBE engine is enabled.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in MongoDB Server

All MongoDB Server vulnerabilities

Recent Use After Free vulnerabilities

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