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CVE-2026-9753 MongoDB CVE debrief

The $_internalApplyOplogUpdate aggregation pipeline stage can be used to execute a document diff containing a malformed binary diff to return memory out-of-bounds or crash the server. $_internalApplyOplogUpdate can be executed by any authenticated user with access to the aggregate command.

Vendor
MongoDB
Product
MongoDB Server
CVSS
HIGH 7.2
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-09
Original CVE updated
2026-06-18
Advisory published
2026-06-09
Advisory updated
2026-06-18

Who should care

Users of MongoDB should be aware of this HIGH severity vulnerability, which has a CVSS score of 7.2. An authenticated user with access to the aggregate command can exploit this vulnerability.

Technical summary

The $_internalApplyOplogUpdate aggregation pipeline stage is vulnerable to a memory out-of-bounds or crash issue when a malformed binary diff is executed. This can be done by any authenticated user with access to the aggregate command.

Defensive priority

HIGH

Recommended defensive actions

  • Apply the necessary patches or updates to prevent exploitation of this vulnerability.
  • Restrict access to the aggregate command to only authorized users.

Evidence notes

Vendor and product information is based on evidence from the source item.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-9753 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-9753

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-9753 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-9753

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.