What’s Vulnerable › Vulnerabilities

CVE-2019-9023

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 9.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2019-02-22 · updated 2026-06-17
• Weakness: CWE-125

Description

An issue was discovered in PHP before 5.6.40, 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.1. A number of heap-based buffer over-read instances are present in mbstring regular expression functions when supplied with invalid multibyte data. These occur in ext/mbstring/oniguruma/regcomp.c, ext/mbstring/oniguruma/regexec.c, ext/mbstring/oniguruma/regparse.c, ext/mbstring/oniguruma/enc/unicode.c, and ext/mbstring/oniguruma/src/utf32_be.c when a multibyte regular expression pattern contains invalid multibyte sequences.

Affected products

• Canonical Ubuntu Linux: 12.04, 14.04, 16.04
• Debian Linux: 9.0
• NetApp Storage Automation Store: all versions
• openSUSE Leap: 42.3
• PHP: before 5.6.40; from 7.0.0 before 7.1.26; from 7.2.0 before 7.2.14; from 7.3.0 before 7.3.1 — fixed in 5.6.40, 7.1.26, 7.2.14, 7.3.1

How to fix

Upgrade to a fixed version: PHP 5.6.40, 7.1.26, 7.2.14, 7.3.1. Check the vendor advisory for mitigations.

References

• http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00083.html
• http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00104.html
• http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00041.html
• http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00044.html
• http://www.securityfocus.com/bid/107156
• https://access.redhat.com/errata/RHSA-2019:2519
• https://access.redhat.com/errata/RHSA-2019:3299
• https://bugs.php.net/bug.php?id=77370
• https://bugs.php.net/bug.php?id=77371
• https://bugs.php.net/bug.php?id=77381
• https://bugs.php.net/bug.php?id=77382
• https://bugs.php.net/bug.php?id=77385

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