CVE-2017-9224

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2017-05-24 · updated 2026-06-17
Weakness: CWE-125

Description

An issue was discovered in Oniguruma 6.2.0, as used in Oniguruma-mod in Ruby through 2.4.1 and mbstring in PHP through 7.1.5. A stack out-of-bounds read occurs in match_at() during regular expression searching. A logical error involving order of validation and access in match_at() could result in an out-of-bounds read from a stack buffer.

Affected products

Oniguruma Project Oniguruma: 6.2.0
PHP: before 5.6.31; from 7.0.0 before 7.0.21; from 7.1.0 before 7.1.7 — fixed in 5.6.31, 7.0.21, 7.1.7

How to fix

Upgrade to a fixed version: PHP 5.6.31, 7.0.21, 7.1.7. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/101244
https://access.redhat.com/errata/RHSA-2018:1296
https://github.com/kkos/oniguruma/commit/690313a061f7a4fa614ec5cc8368b4f2284e059b
https://github.com/kkos/oniguruma/issues/57
http://www.securityfocus.com/bid/101244
https://access.redhat.com/errata/RHSA-2018:1296
https://github.com/kkos/oniguruma/commit/690313a061f7a4fa614ec5cc8368b4f2284e059b
https://github.com/kkos/oniguruma/issues/57

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