How severe is CVE-2019-20454?

CVE-2019-20454 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-2019-20454 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-20454?

CVE-2019-20454 primarily affects Pcre Pcre2. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-20454?

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-2019-20454 published?

CVE-2019-20454 was published on 2020-02-14 and last updated on 2026-06-17.

CVE-2019-20454

CVE-2019-20454 is a high-severity vulnerability in Pcre Pcre2 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: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Pcre Pcre2
Published: 2020-02-14
Last modified: 2026-06-17

Description

An out-of-bounds read was discovered in PCRE before 10.34 when the pattern \X is JIT compiled and used to match specially crafted subjects in non-UTF mode. Applications that use PCRE to parse untrusted input may be vulnerable to this flaw, which would allow an attacker to crash the application. The flaw occurs in do_extuni_no_utf in pcre2_jit_compile.c.

Frequently asked questions

What is CVE-2019-20454?: An out-of-bounds read was discovered in PCRE before 10.34 when the pattern \X is JIT compiled and used to match specially crafted subjects in non-UTF mode. Applications that use PCRE to parse untrusted input may be vulnerable to this flaw, which would allow an attacker to crash the application. The flaw occurs in do_extuni_no_utf in pcre2_jit_compile.c.
How severe is CVE-2019-20454?: CVE-2019-20454 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-2019-20454 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-20454?: CVE-2019-20454 primarily affects Pcre Pcre2. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-20454?: 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-2019-20454 published?: CVE-2019-20454 was published on 2020-02-14 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:pcre:pcre2:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
cpe:2.3:a:splunk:universal_forwarder:*:*:*:*:*:*:*:*
cpe:2.3:a:splunk:universal_forwarder:9.1.0:*:*:*:*:*:*:*

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