How severe is CVE-2019-19204?

CVE-2019-19204 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-2019-19204 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-19204?

CVE-2019-19204 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-2019-19204?

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-2019-19204 published?

CVE-2019-19204 was published on 2019-11-21 and last updated on 2026-06-17.

CVE-2019-19204

CVE-2019-19204 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Oniguruma Project Oniguruma
Published: 2019-11-21
Last modified: 2026-06-17

Description

An issue was discovered in Oniguruma 6.x before 6.9.4_rc2. In the function fetch_interval_quantifier (formerly known as fetch_range_quantifier) in regparse.c, PFETCH is called without checking PEND. This leads to a heap-based buffer over-read.

Frequently asked questions

What is CVE-2019-19204?: An issue was discovered in Oniguruma 6.x before 6.9.4_rc2. In the function fetch_interval_quantifier (formerly known as fetch_range_quantifier) in regparse.c, PFETCH is called without checking PEND. This leads to a heap-based buffer over-read.
How severe is CVE-2019-19204?: CVE-2019-19204 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-2019-19204 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-19204?: CVE-2019-19204 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-2019-19204?: 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-2019-19204 published?: CVE-2019-19204 was published on 2019-11-21 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:oniguruma_project:oniguruma:*:*:*:*:*:*:*:*
cpe:2.3:a:oniguruma_project:oniguruma:6.9.4:rc1:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*

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