How severe is CVE-2026-9748?

CVE-2026-9748 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-9748 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-9748?

CVE-2026-9748 affects Mongodb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-9748?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-9748 have an EU (EUVD) identifier?

Yes. CVE-2026-9748 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35864.

When was CVE-2026-9748 published?

CVE-2026-9748 was published on 2026-06-09 and last updated on 2026-06-17.

CVE-2026-9748

CVE-2026-9748 is a medium-severity vulnerability in Mongodb with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-617.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 7.1
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35864
Weakness: CWE-617
Affected product: Mongodb
Published: 2026-06-09
Last modified: 2026-06-17

Description

The $_internalConvertBucketIndexStats stage used PauseExecution as a way to signal "skip this document" when an index stats conversion failed. But PauseExecution is not a general purpose skip mechanism, but rather a TeeBuffer-internal signal used solely by $facet to coordinate its sub-pipelines. When this stage is placed before $facet in a pipeline, TeeBuffer receives the unexpected PauseExecution from upstream and hits a hard invariant assertion, crashing mongod.

Frequently asked questions

What is CVE-2026-9748?: The $_internalConvertBucketIndexStats stage used PauseExecution as a way to signal "skip this document" when an index stats conversion failed. But PauseExecution is not a general purpose skip mechanism, but rather a TeeBuffer-internal signal used solely by $facet to coordinate its sub-pipelines. When this stage is placed before $facet in a pipeline, TeeBuffer receives the unexpected PauseExecution from upstream and hits a hard invariant assertion, crashing mongod.
How severe is CVE-2026-9748?: CVE-2026-9748 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-9748 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-9748?: CVE-2026-9748 affects Mongodb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-9748?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-9748 have an EU (EUVD) identifier?: Yes. CVE-2026-9748 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35864.
When was CVE-2026-9748 published?: CVE-2026-9748 was published on 2026-06-09 and last updated on 2026-06-17.

References

https://jira.mongodb.org/browse/SERVER-123951

Affected products (1)

cpe:2.3:a:mongodb:mongodb:*:*:*:*:*:*:*:*

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