CVE-2017-9226

Exp

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.

Published: 2017-05-24 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-9226 is rated High Exploit Risk (82.2/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.24%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2017-9226

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2017-9226

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-26 1.08% 1.24% +0.16%
2 2026-05-14 1.04% 1.08% +0.04%
3 2026-03-04 — 1.04% —

Full EPSS history (56 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-9226

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2017-9226

OS Trackers for CVE-2017-9226

vendor priority summary link
debian not yet assigned CVE-2017-9226 not yet assigned priority: Debian including 1 source packages (libonig), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-9226
redhat medium — https://access.redhat.com/security/cve/CVE-2017-9226
suse medium CVE-2017-9226 severity moderate: SUSE including 208 source package names (apache2-mod_php5-5.2.14-0.7.30.110.1, apache2-mod_php5-5.5.14-108.1, …), 302 product×package rows across 12 product lines (SUSE Linux Enterprise Module for Web and Scripting 12, SUSE Linux Enterprise Server 11 SP1 for Teradata, … (12 product lines)): Fixed 300, Known Not Affected 2. https://www.suse.com/security/cve/CVE-2017-9226/
ubuntu medium CVE-2017-9226 medium priority: Ubuntu including 4 source packages (libonig, php5, php7.0, php7.1), 25 status rows across 7 suites (artful, bionic, trusty, upstream, xenial, yakkety, zesty): DNE 11, released 6, needs-triage 4, ignored 3, not-affected 1. https://ubuntu.com/security/CVE-2017-9226

Affected software / configurations for CVE-2017-9226

Vendor Product Version Raw CPE
oniguruma_project oniguruma 6.2.0 cpe:2.3:a:oniguruma_project:oniguruma:6.2.0:*:*:*:*:*:*:*
php php < 5.6.31 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php >= 7.0.0, < 7.0.21 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php >= 7.1.0, < 7.1.7 cpe:2.3:a:php:php:*:*:*:*:*:*:*:*

References for CVE-2017-9226

cvelogic Threat Intelligence