Ruby 2.4.0 Onigmo regparse.c parse_char_class Regular Expression input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability has been found in Ruby 2.4.0 and classified as problematic. The impacted element is the function parse_char_class of the file regparse.c of the component Onigmo. Performing a manipulation as part of Regular Expression results in input validation. This vulnerability is cataloged as CVE-2017-6181. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Ruby 2.4.0 (Programming Language Software). It has been classified as problematic. This affects the function parse_char_class of the file regparse.c of the component Onigmo. The manipulation as part of a Regular Expression leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on availability. The summary by CVE is:

The parse_char_class function in regparse.c in the Onigmo (aka Oniguruma-mod) regular expression library, as used in Ruby 2.4.0, allows remote attackers to cause a denial of service (deep recursion and application crash) via a crafted regular expression.

The bug was discovered 02/20/2017. The weakness was shared 04/03/2017 (Website). The advisory is shared at bugs.ruby-lang.org. This vulnerability is uniquely identified as CVE-2017-6181 since 02/21/2017. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 42 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 111873 (Photon OS 1.0: Libxml2 / Ncurses / Openldap / Ruby PHSA-2017-0024 (deprecated)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family PhotonOS Local Security Checks and running in the context l.

A possible mitigation has been published 4 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (111873) and SecurityFocus (BID 97304†). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 111873
Nessus Name: Photon OS 1.0: Libxml2 / Ncurses / Openldap / Ruby PHSA-2017-0024 (deprecated)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

02/20/2017 🔍
02/21/2017 +1 days 🔍
04/03/2017 +41 days 🔍
04/03/2017 +0 days 🔍
04/03/2017 +0 days 🔍
04/03/2017 +0 days 🔍
07/13/2017 +101 days 🔍
08/17/2018 +400 days 🔍
11/24/2022 +1560 days 🔍

Sourcesinfo

Advisory: 13234
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-6181 (🔍)
GCVE (CVE): GCVE-0-2017-6181
GCVE (VulDB): GCVE-100-99249
SecurityFocus: 97304 - Ruby CVE-2017-6181 Denial of Service Vulnerability
OSVDB: - CVE-2017-6181 - Onigmo - Denial of Service Issue

Entryinfo

Created: 04/03/2017 16:59
Updated: 11/24/2022 18:28
Changes: 04/03/2017 16:59 (70), 08/25/2020 12:46 (6), 11/24/2022 18:28 (3)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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