How severe is CVE-2018-9336?

CVE-2018-9336 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-9336 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-9336?

CVE-2018-9336 primarily affects Openvpn. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-9336?

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-2018-9336 published?

CVE-2018-9336 was published on 2018-05-01 and last updated on 2026-06-17.

CVE-2018-9336

CVE-2018-9336 is a high-severity vulnerability in Openvpn with a CVSS 3.x base score of 7.8. 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-415.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-415
Affected product: Openvpn
Published: 2018-05-01
Last modified: 2026-06-17

Description

openvpnserv.exe (aka the interactive service helper) in OpenVPN 2.4.x before 2.4.6 allows a local attacker to cause a double-free of memory by sending a malformed request to the interactive service. This could cause a denial-of-service through memory corruption or possibly have unspecified other impact including privilege escalation.

Frequently asked questions

What is CVE-2018-9336?: openvpnserv.exe (aka the interactive service helper) in OpenVPN 2.4.x before 2.4.6 allows a local attacker to cause a double-free of memory by sending a malformed request to the interactive service. This could cause a denial-of-service through memory corruption or possibly have unspecified other impact including privilege escalation.
How severe is CVE-2018-9336?: CVE-2018-9336 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-9336 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-9336?: CVE-2018-9336 primarily affects Openvpn. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-9336?: 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-2018-9336 published?: CVE-2018-9336 was published on 2018-05-01 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
cpe:2.3:o:slackware:slackware_linux:13.0:*:*:*:*:*:*:*
cpe:2.3:o:slackware:slackware_linux:13.1:*:*:*:*:*:*:*
cpe:2.3:o:slackware:slackware_linux:13.37:*:*:*:*:*:*:*
cpe:2.3:o:slackware:slackware_linux:14.0:*:*:*:*:*:*:*
cpe:2.3:o:slackware:slackware_linux:14.1:*:*:*:*:*:*:*

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