How severe is CVE-2019-16163?

CVE-2019-16163 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-2019-16163 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-16163?

CVE-2019-16163 primarily affects Oniguruma Project Oniguruma. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-16163?

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-2019-16163 published?

CVE-2019-16163 was published on 2019-09-09 and last updated on 2026-06-17.

CVE-2019-16163

CVE-2019-16163 is a high-severity vulnerability in Oniguruma Project Oniguruma 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-674.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-674
Affected product: Oniguruma Project Oniguruma
Published: 2019-09-09
Last modified: 2026-06-17

Description

Oniguruma before 6.9.3 allows Stack Exhaustion in regcomp.c because of recursion in regparse.c.

Frequently asked questions

What is CVE-2019-16163?: Oniguruma before 6.9.3 allows Stack Exhaustion in regcomp.c because of recursion in regparse.c.
How severe is CVE-2019-16163?: CVE-2019-16163 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-2019-16163 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-16163?: CVE-2019-16163 primarily affects Oniguruma Project Oniguruma. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-16163?: 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-2019-16163 published?: CVE-2019-16163 was published on 2019-09-09 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:oniguruma_project:oniguruma:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*

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