How severe is CVE-2019-18934?

CVE-2019-18934 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2019-18934 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-18934?

CVE-2019-18934 primarily affects Nlnetlabs Unbound. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-18934?

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-2019-18934 published?

CVE-2019-18934 was published on 2019-11-19 and last updated on 2026-06-17.

CVE-2019-18934

CVE-2019-18934 is a high-severity vulnerability in Nlnetlabs Unbound with a CVSS 3.x base score of 7.3. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 6.8
EPSS exploit prediction: 3% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Nlnetlabs Unbound
Published: 2019-11-19
Last modified: 2026-06-17

Description

Unbound 1.6.4 through 1.9.4 contain a vulnerability in the ipsec module that can cause shell code execution after receiving a specially crafted answer. This issue can only be triggered if unbound was compiled with `--enable-ipsecmod` support, and ipsecmod is enabled and used in the configuration.

Frequently asked questions

What is CVE-2019-18934?: Unbound 1.6.4 through 1.9.4 contain a vulnerability in the ipsec module that can cause shell code execution after receiving a specially crafted answer. This issue can only be triggered if unbound was compiled with `--enable-ipsecmod` support, and ipsecmod is enabled and used in the configuration.
How severe is CVE-2019-18934?: CVE-2019-18934 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2019-18934 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-18934?: CVE-2019-18934 primarily affects Nlnetlabs Unbound. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-18934?: 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-2019-18934 published?: CVE-2019-18934 was published on 2019-11-19 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

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