How severe is CVE-2026-18693?

CVE-2026-18693 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2026-18693 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-18693?

CVE-2026-18693 primarily affects Mongodb. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-18693?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-18693 published?

CVE-2026-18693 was published on 2026-08-11 and last updated on 2026-09-16.

CVE-2026-18693

CVE-2026-18693 is a high-severity vulnerability in Mongodb with a CVSS 3.x base score of 7.6. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.6)
CVSS v4: 7.2
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Mongodb
Published: 2026-08-11
Last modified: 2026-09-16

Description

An issue in MongoDB Server's handling of timeseries collections could allow an authenticated user with write privileges to cause an internal data structure to become inconsistent through certain document insertions. A subsequent insert into the affected bucket could then result in the server accessing memory outside its intended bounds, potentially causing a server crash (denial of service), exposure of limited memory contents, or memory corruption.

Frequently asked questions

What is CVE-2026-18693?: An issue in MongoDB Server's handling of timeseries collections could allow an authenticated user with write privileges to cause an internal data structure to become inconsistent through certain document insertions. A subsequent insert into the affected bucket could then result in the server accessing memory outside its intended bounds, potentially causing a server crash (denial of service), exposure of limited memory contents, or memory corruption.
How severe is CVE-2026-18693?: CVE-2026-18693 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2026-18693 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-18693?: CVE-2026-18693 primarily affects Mongodb. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-18693?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-18693 published?: CVE-2026-18693 was published on 2026-08-11 and last updated on 2026-09-16.

References

https://jira.mongodb.org/browse/SERVER-129994

Affected products (4)

cpe:2.3:a:mongodb:mongodb:*:*:*:*:*:*:*:*
cpe:2.3:a:mongodb:mongodb:9.0.0:alpha0:*:*:-:-:*:*
cpe:2.3:a:mongodb:mongodb:9.0.0:alpha1:*:*:-:-:*:*
cpe:2.3:a:mongodb:mongodb:9.1.0:alpha0:*:*:-:-:*:*

More vulnerabilities in Mongodb

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Threat intelligence

Threat-intel indicators referencing this CVE:

138.197.130.35 (ipv4-addr)
18.228.228.159 (ipv4-addr)
3.19.213.118 (ipv4-addr)