CVE-2019-20454

Name: CVE-2019-20454
Creator: NVD / NIST
Published: 2020-02-14T14:15:10.593+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.52%

Last modified Jun 17, 2026

CVE-2019-20454 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 1.52% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.52%

71.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-125

Affected Software

Vendor	Product	Versions
Pcre	Pcre2	>= 10.31, < 10.34
Fedoraproject	Fedora	31
Splunk	Universal Forwarder	>= 8.2.0, < 8.2.12
Splunk	Universal Forwarder	>= 9.0.0, < 9.0.6
Splunk	Universal Forwarder	9.1.0

References

https://bugs.exim.org/show_bug.cgi?id=2421Issue Tracking, Permissions Required, Third Party Advisory
https://bugs.php.net/bug.php?id=78338Exploit, Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1735494Issue Tracking, Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/03/msg00014.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OQRAHYHLRNMBTPR3KXVM27NSZP3KTOPI/Mailing List, Third Party Advisory
https://security.gentoo.org/glsa/202006-16Third Party Advisory
https://vcs.pcre.org/pcre2?view=revision&revision=1092Broken Link, Patch
https://bugs.exim.org/show_bug.cgi?id=2421Issue Tracking, Permissions Required, Third Party Advisory
https://bugs.php.net/bug.php?id=78338Exploit, Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1735494Issue Tracking, Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/03/msg00014.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OQRAHYHLRNMBTPR3KXVM27NSZP3KTOPI/Mailing List, Third Party Advisory
https://security.gentoo.org/glsa/202006-16Third Party Advisory
https://vcs.pcre.org/pcre2?view=revision&revision=1092Broken Link, Patch

Timeline

Published: Feb 14, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-20454?

How severe is CVE-2019-20454?

CVE-2019-20454 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.52% probability of exploitation in the next 30 days.

How do I fix CVE-2019-20454?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-20454?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST