How severe is CVE-2018-18066?

CVE-2018-18066 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-18066 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18066?

CVE-2018-18066 primarily affects Net-snmp. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-18066?

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-2018-18066 published?

CVE-2018-18066 was published on 2018-10-08 and last updated on 2026-06-17.

CVE-2018-18066

CVE-2018-18066 is a high-severity vulnerability in Net-snmp with a CVSS 3.x base score of 7.5. 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Net-snmp
Published: 2018-10-08
Last modified: 2026-06-17

Description

snmp_oid_compare in snmplib/snmp_api.c in Net-SNMP before 5.8 has a NULL Pointer Exception bug that can be used by an unauthenticated attacker to remotely cause the instance to crash via a crafted UDP packet, resulting in Denial of Service.

Frequently asked questions

What is CVE-2018-18066?: snmp_oid_compare in snmplib/snmp_api.c in Net-SNMP before 5.8 has a NULL Pointer Exception bug that can be used by an unauthenticated attacker to remotely cause the instance to crash via a crafted UDP packet, resulting in Denial of Service.
How severe is CVE-2018-18066?: CVE-2018-18066 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-18066 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18066?: CVE-2018-18066 primarily affects Net-snmp. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-18066?: 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-2018-18066 published?: CVE-2018-18066 was published on 2018-10-08 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:net-snmp:net-snmp:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:hyper_converged_infrastructure:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:storagegrid_webscale:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:data_ontap:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:e-series_santricity_os_controller:*:*:*:*:*:*:*:*
cpe:2.3:o:netapp:solidfire_element_os:-:*:*:*:*:*:*:*

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