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TI-2019-14683 Aliases CVE-2019-20454GHSA-6wcm-vmc4-h93p

An out-of-bounds read was discovered in PCRE before 10.34 when the pattern \X is JIT…

Priority LOW 36CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 3 fixed, 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01561 75th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 2 advisoriesRed Hat: 3 fixed, 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:pcre:pcre2:*:*:*:*:*:*:*:*10.31 to before 10.34VulnerablePCRE
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*31VulnerableFedoraproject
cpe:2.3:a:splunk:universal_forwarder:*:*:*:*:*:*:*:*8.2.0 to before 8.2.12; 9.0.0 to before 9.0.6VulnerableSplunk
cpe:2.3:a:splunk:universal_forwarder:9.1.0:*:*:*:*:*:*:*9.1.0VulnerableSplunk
  • cpe:2.3:a:pcre:pcre2:*:*:*:*:*:*:*:* Versions 10.31 to before 10.34 Vulnerable ·PCRE
  • cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
  • cpe:2.3:a:splunk:universal_forwarder:*:*:*:*:*:*:*:* Versions 8.2.0 to before 8.2.12; 9.0.0 to before 9.0.6 Vulnerable ·Splunk
  • cpe:2.3:a:splunk:universal_forwarder:9.1.0:*:*:*:*:*:*:* Versions 9.1.0 Vulnerable ·Splunk

Remediation

Red Hat 2 advisories

  • RHSA-2020:4539 Released 2020-11-04 · Red Hat rating Moderate
    pcre2 security and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) pcre2-tools-10.32-2.el8
    • Red Hat Enterprise Linux BaseOS (v. 8) pcre2-10.32-2.el8, pcre2-devel-10.32-2.el8, pcre2-utf16-10.32-2.el8 +1
  • RHSA-2020:3662 Released 2020-09-08 · Red Hat rating Moderate
    php:7.3 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) apcu-panel-5.1.17-1.module+el8.1.0+3189+a1bff096.noarch::php:7.3, libzip-1.5.2-1.module+el8.1.0+3189+a1bff096.aarch64::php:7.3, libzip-1.5.2-1.module+el8.1.0+3189+a1bff096.ppc64le::php:7.3 +47

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat JBoss Enterprise Web Server 1AffectedNo fix planned: Out of support scope
Red Hat JBoss Enterprise Web Server 2AffectedNo fix planned: Out of support scope
Red Hat JBoss Web Server 3AffectedNo fix planned: Out of support scope
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2020:4539
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2020:3662
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2020:4539
Not affected: 4 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat JBoss Core Services
  • Red Hat Software Collections

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-20454
  2. 2026-10-03 Alias added: GHSA-6wcm-vmc4-h93p
  3. 2026-11-02 CISA SSVC decision points changed

References

Exploit 1

Patch 2

Advisory 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences