OpenSSL up to 0.9.8c ASN.1 Public Key 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.
6.5	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical has been found in OpenSSL. Affected by this issue is some unknown functionality of the component ASN.1 Public Key Handler. This manipulation causes resource management. This vulnerability is registered as CVE-2006-2940. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in OpenSSL (Network Encryption Software). Affected by this vulnerability is some unknown processing of the component ASN.1 Public Key Handler. The manipulation with an unknown input leads to a resource management vulnerability. The CWE definition for the vulnerability is CWE-399. As an impact it is known to affect availability. The summary by CVE is:

OpenSSL 0.9.7 before 0.9.7l, 0.9.8 before 0.9.8d, and earlier versions allows attackers to cause a denial of service (CPU consumption) via parasitic public keys with large (1) "public exponent" or (2) "public modulus" values in X.509 certificates that require extra time to process when using RSA signature verification.

The issue has been introduced in 12/23/1998. The weakness was published 09/28/2006 by Dr. S. N. Henson with Open Network Security (Website). It is possible to read the advisory at openssl.org. This vulnerability is known as CVE-2006-2940 since 06/09/2006. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 2836 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 22881 (Debian DSA-1195-1 : openssl096 - denial of service (multiple)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 185030 (HP-UX Running OpenSSL Multiple Vulnerabilities (HPSBUX02174)).

Upgrading eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at openssl.org. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published 2 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (29230), Tenable (22881), SecurityFocus (BID 20247†), OSVDB (29261†) and Secunia (SA22500†). Similar entries are available at VDB-1786, VDB-1803, VDB-1858 and VDB-1857. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Network Encryption Software

Name

• OpenSSL

Version

• 0.9.1c
• 0.9.2b
• 0.9.3
• 0.9.3a
• 0.9.4
• 0.9.5
• 0.9.5a
• 0.9.6
• 0.9.6a
• 0.9.6b
• 0.9.6c
• 0.9.6d
• 0.9.6e
• 0.9.6f
• 0.9.6g
• 0.9.6h
• 0.9.6i
• 0.9.6j
• 0.9.6k
• 0.9.6l
• 0.9.6m
• 0.9.7
• 0.9.7a
• 0.9.7b
• 0.9.7c
• 0.9.7d
• 0.9.7e
• 0.9.7f
• 0.9.7g
• 0.9.7h
• 0.9.7i
• 0.9.7j
• 0.9.7k
• 0.9.8
• 0.9.8a
• 0.9.8b
• 0.9.8c

License

• open-source

Support

• end of life (old version)

Website

• Product: https://www.openssl.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 6.5

VulDB Base Score: 7.5
VulDB Temp Score: 6.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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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: Proof-of-Concept

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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

Nessus ID: 22881
Nessus Name: Debian DSA-1195-1 : openssl096 - denial of service (multiple)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍
Nessus Port: 🔍

OpenVAS ID: 57478
OpenVAS Name: Debian Security Advisory DSA 1185-1 (openssl)
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: 🔍

Patch: openssl.org

Timelineinfo

12/23/1998 🔍
06/09/2006 +2725 days 🔍
09/28/2006 +111 days 🔍
09/28/2006 +0 days 🔍
09/28/2006 +0 days 🔍
09/28/2006 +0 days 🔍
09/29/2006 +0 days 🔍
09/29/2006 +0 days 🔍
10/10/2006 +11 days 🔍
10/20/2006 +10 days 🔍
04/23/2026 +7125 days 🔍

Sourcesinfo

Product: openssl.org

Advisory: openssl.org
Researcher: Dr. S. N. Henson
Organization: Open Network Security
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2006-2940 (🔍)
GCVE (CVE): GCVE-0-2006-2940
GCVE (VulDB): GCVE-100-2575

OVAL: 🔍

X-Force: 29230 - OpenSSL X.509 public key denial of service, Medium Risk
SecurityFocus: 20247 - OpenSSL Public Key Processing Denial of Service Vulnerability
Secunia: 22500 - Debian update for openssl096, Highly Critical
OSVDB: 29261 - OpenSSL Crafted Public Key CPU Consumption DoS
SecurityTracker: 1016943
Vupen: ADV-2006-3820

See also: 🔍

Entryinfo

Created: 09/29/2006 10:44
Updated: 04/23/2026 04:05
Changes: 09/29/2006 10:44 (90), 04/27/2019 15:38 (8), 04/23/2026 04:05 (17)
Complete: 🔍
Cache ID: 216::103

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