CVE-2017-9229: Oniguruma Project Oniguruma

High severity, CVSS 7.5. EPSS: 5.1% chance of exploitation in the next 30 days.

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 SIGSEGV occurs in left_adjust_char_head() during regular expression compilation. Invalid handling of reg->dmax in forward_search_range() could result in an invalid pointer dereference, normally as an immediate denial-of-service condition.

Affected products

• Oniguruma Project Oniguruma: version 6.2.0 only
• PHP PHP: up to and including 7.1.5; from 5.6.0, before 5.6.31 (fixed in 5.6.31); from 7.0.0, before 7.0.21 (fixed in 7.0.21); from 7.1.0, before 7.1.7 (fixed in 7.1.7)
• Ruby-Lang Ruby: up to and including 2.4.1

Published 2017-05-24. Last modified 2026-06-17.