How severe is CVE-2023-22359?

CVE-2023-22359 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2023-22359 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-22359?

CVE-2023-22359 primarily affects Checkmk. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-22359?

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

When was CVE-2023-22359 published?

CVE-2023-22359 was published on 2023-06-26 and last updated on 2026-06-17.

CVE-2023-22359

CVE-2023-22359 is a medium-severity vulnerability in Checkmk with a CVSS 3.x base score of 4.3. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (39th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Checkmk
Published: 2023-06-26
Last modified: 2026-06-17

Description

User enumeration in Checkmk <=2.2.0p4 allows an authenticated attacker to enumerate usernames.

Frequently asked questions

What is CVE-2023-22359?: User enumeration in Checkmk <=2.2.0p4 allows an authenticated attacker to enumerate usernames.
How severe is CVE-2023-22359?: CVE-2023-22359 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2023-22359 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-22359?: CVE-2023-22359 primarily affects Checkmk. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-22359?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-22359 published?: CVE-2023-22359 was published on 2023-06-26 and last updated on 2026-06-17.

References

https://checkmk.com/werk/15890

Affected products (14)

cpe:2.3:a:checkmk:checkmk:2.2.0:-:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b1:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b2:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b3:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b4:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b5:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b6:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b7:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:b8:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:i1:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:p1:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:p2:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:p3:*:*:*:*:*:*
cpe:2.3:a:checkmk:checkmk:2.2.0:p4:*:*:*:*:*:*

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