Ruby up to 1.9.0 Safe Level input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in Ruby up to 1.9.0 (Programming Language Software). It has been classified as critical. Affected is an unknown functionality of the component Safe Level. The manipulation with an unknown input 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 confidentiality, integrity, and availability.

The bug was discovered 08/08/2008. The weakness was shared 08/12/2008 (Website). The advisory is available at This vulnerability is traded as CVE-2008-3657 since 08/12/2008. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are unknown but a public exploit is available.

A public exploit has been developed in Ruby. The exploit is shared for download at It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 4 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 34502 (CentOS 4 / 5 : ruby (CESA-2008:0897)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CentOS Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 165649 (SUSE Enterprise Linux Security Update dhcp-client (SUSE-SA:2009:037)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 3 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (46108) and Tenable (34502). The entries 3810, 23858, 30376 and 40710 are related to this item.






CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
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Class: Input validation
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Programming Language: 🔍
Download: 🔍

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Nessus ID: 34502
Nessus Name: CentOS 4 / 5 : ruby (CESA-2008:0897)
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OpenVAS ID: 61773
OpenVAS Name: Debian Security Advisory DSA 1651-1 (ruby1.8)
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

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08/08/2008 🔍
08/11/2008 +3 days 🔍
08/12/2008 +1 days 🔍
08/12/2008 +0 days 🔍
08/12/2008 +0 days 🔍
08/12/2008 +0 days 🔍
08/12/2008 +0 days 🔍
10/12/2008 +61 days 🔍
10/28/2008 +16 days 🔍
10/28/2008 +0 days 🔍
03/17/2015 +2331 days 🔍
08/18/2019 +1615 days 🔍


Status: Confirmed
Confirmation: 🔍

CVE: CVE-2008-3657 (🔍)

X-Force: 46108
SecurityTracker: 1020652
Vulnerability Center: 19679 - Ruby dl Module Allows Bypassing of Safe Levels, Medium
SecurityFocus: 30644 - Ruby Multiple Security Bypass and Denial of Service Vulnerabilities
Secunia: 31430
OSVDB: 47472 - CVE-2008-3657 - Ruby - Security Bypass Issue
Vupen: ADV-2008-2334

scip Labs:
See also: 🔍


Created: 03/17/2015 12:19 PM
Updated: 08/18/2019 09:06 AM
Changes: 03/17/2015 12:19 PM (79), 08/18/2019 09:06 AM (13)
Complete: 🔍


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