Ruby up to 2.2.9/2.3.6/2.4.3/2.5.0 WEBrick Server HTTP Request resource management

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3	$0-$5k	0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Ruby up to 2.2.9/2.3.6/2.4.3/2.5.0. Affected by this vulnerability is an unknown functionality of the component WEBrick Server. Performing a manipulation as part of HTTP Request results in resource management. This vulnerability is known as CVE-2018-8777. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Ruby up to 2.2.9/2.3.6/2.4.3/2.5.0 (Programming Language Software). It has been classified as problematic. This affects an unknown code of the component WEBrick Server. The manipulation as part of a HTTP Request leads to a resource management vulnerability. CWE is classifying the issue as CWE-399. This is going to have an impact on availability. The summary by CVE is:

In Ruby before 2.2.10, 2.3.x before 2.3.7, 2.4.x before 2.4.4, 2.5.x before 2.5.1, and 2.6.0-preview1, an attacker can pass a large HTTP request with a crafted header to WEBrick server or a crafted body to WEBrick server/handler and cause a denial of service (memory consumption).

The bug was discovered 03/28/2018. The weakness was published 04/03/2018 (Website). The advisory is shared at ruby-lang.org. This vulnerability is uniquely identified as CVE-2018-8777 since 03/19/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 6 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 110551 (Ubuntu 14.04 LTS / 16.04 LTS / 17.10 : ruby1.9.1, ruby2.0, ruby2.3 vulnerabilities (USN-3685-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 237072 (Red Hat Update for rh-ruby25-ruby (RHSA-2018:3731)).

Upgrading to version 2.2.10, 2.3.7, 2.4.4, 2.5.1 or 2.6.0-preview1 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 Tenable (110551), SecurityFocus (BID 103683†) and CERT Bund (WID-SEC-2023-1111). Similar entries are available at VDB-114428, VDB-114429, VDB-114430 and VDB-114431. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Open Source Ruby
• Open Source Arch Linux

Productinfo

Type

• Programming Language Software

Name

• Ruby

Version

• 2.0
• 2.1
• 2.2
• 2.2.0
• 2.2.1
• 2.2.2
• 2.2.3
• 2.2.4
• 2.2.5
• 2.2.6
• 2.2.7
• 2.2.8
• 2.2.9
• 2.3
• 2.3.0
• 2.3.1
• 2.3.2
• 2.3.3
• 2.3.4
• 2.3.5
• 2.3.6
• 2.4
• 2.4.0
• 2.4.1
• 2.4.2
• 2.4.3
• 2.5.0

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Resource management
CWE: CWE-399 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 110551
Nessus Name: Ubuntu 14.04 LTS / 16.04 LTS / 17.10 : ruby1.9.1, ruby2.0, ruby2.3 vulnerabilities (USN-3685-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 860813
OpenVAS Name: Debian LTS Advisory ([SECURITY] [DLA 1358-1] ruby1.9.1 security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Ruby 2.2.10/2.3.7/2.4.4/2.5.1/2.6.0-preview1

Timelineinfo

03/19/2018 🔍
03/28/2018 +9 days 🔍
03/28/2018 +0 days 🔍
04/03/2018 +6 days 🔍
04/03/2018 +0 days 🔍
04/04/2018 +1 days 🔍
06/13/2018 +70 days 🔍
06/15/2018 +2 days 🔍
05/10/2026 +2885 days 🔍

Sourcesinfo

Advisory: USN-3685-1
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-8777 (🔍)
GCVE (CVE): GCVE-0-2018-8777
GCVE (VulDB): GCVE-100-115665

OVAL: 🔍

SecurityFocus: 103683 - Ruby CVE-2018-8777 Denial of Service Vulnerability
SecurityTracker: 1042004
CERT Bund: WID-SEC-2023-1111 - Ruby: Mehrere Schwachstellen

See also: 🔍

Entryinfo

Created: 04/04/2018 09:54
Updated: 05/10/2026 01:34
Changes: 04/04/2018 09:54 (77), 01/21/2020 09:03 (6), 02/08/2021 11:39 (3), 02/26/2023 14:34 (3), 02/26/2023 14:39 (1), 05/10/2026 01:34 (21)
Complete: 🔍
Cache ID: 216::103

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

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