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 heap out-of-bounds write or read occurs in next_state_val() during regular expression compilation. Octal numbers larger than 0xff are not handled correctly in fetch_token() and fetch_token_in_cc(). A malformed regular expression containing an octal number in the form of '\700' would produce an invalid code point value larger than 0xff in next_state_val(), resulting in an out-of-bounds write memory corruption.
The product writes data past the end, or before the beginning, of the intended buffer.
| Link | Tags |
|---|---|
| https://github.com/kkos/oniguruma/issues/55 | issue tracking exploit third party advisory |
| https://access.redhat.com/errata/RHSA-2018:1296 | third party advisory vendor advisory |
| https://github.com/kkos/oniguruma/commit/f015fbdd95f76438cd86366467bb2b39870dd7c6 | third party advisory patch |
| https://github.com/kkos/oniguruma/commit/b4bf968ad52afe14e60a2dc8a95d3555c543353a | third party advisory patch |
| http://www.securityfocus.com/bid/101244 | vdb entry third party advisory |