How severe is CVE-2026-59509?

CVE-2026-59509 has a CVSS 4.0 base score of 9.2, rated critical severity.

Is CVE-2026-59509 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-59509?

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

When was CVE-2026-59509 published?

CVE-2026-59509 was published on 2026-07-05 and last updated on 2026-07-06.

CVE-2026-59509

CVE-2026-59509 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.2. 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-20.

Key facts

Severity: Critical (CVSS 4.0 base score 9.2)
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Published: 2026-07-05
Last modified: 2026-07-06

Description

An unauthenticated improper input validation vulnerability in the POST /fetch_cve_data endpoint in cve-search. A remote attacker can manipulate request parameters controlling the MongoDB collection, projected fields, and regular-expression filters to read arbitrary application MongoDB collections. This can expose administrative usernames and password hashes from the mgmt_users collection, enabling offline password cracking and potential administrative account compromise.

Frequently asked questions

What is CVE-2026-59509?: An unauthenticated improper input validation vulnerability in the POST /fetch_cve_data endpoint in cve-search. A remote attacker can manipulate request parameters controlling the MongoDB collection, projected fields, and regular-expression filters to read arbitrary application MongoDB collections. This can expose administrative usernames and password hashes from the mgmt_users collection, enabling offline password cracking and potential administrative account compromise.
How severe is CVE-2026-59509?: CVE-2026-59509 has a CVSS 4.0 base score of 9.2, rated critical severity.
Is CVE-2026-59509 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-59509?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-59509 published?: CVE-2026-59509 was published on 2026-07-05 and last updated on 2026-07-06.

References

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