CVE-2019-20454
CVSS v3
7.5
HIGH
EPSS Score
1.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2020-02-14
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.
Is CVE-2019-20454 actively exploited?
Active exploitation of CVE-2019-20454 has not been confirmed. Its EPSS score was 1.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2019-20454?
CVE-2019-20454 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2019-20454 affecting your environment?
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