OpenBSD OpenSSH up to 4.4 Signal race condition

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in OpenBSD OpenSSH up to 4.4. This issue affects some unknown processing of the component Signal Handler. Executing a manipulation can lead to race condition. This vulnerability appears as CVE-2006-5051. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in OpenBSD OpenSSH up to 4.4 (Connectivity Software) and classified as critical. This vulnerability affects some unknown functionality of the component Signal Handler. The manipulation with an unknown input leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Signal handler race condition in OpenSSH before 4.4 allows remote attackers to cause a denial of service (crash), and possibly execute arbitrary code if GSSAPI authentication is enabled, via unspecified vectors that lead to a double-free.

The bug was discovered 09/12/2008. The weakness was presented 09/29/2006 by Mark Dowd with ISS X-Force (Website). The advisory is available at openssh.org. This vulnerability was named CVE-2006-5051 since 09/27/2006. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

It is declared as proof-of-concept. As 0-day the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 23671 (GLSA-200611-06 : OpenSSH: Multiple Denial of Service vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Gentoo Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 38560 (OpenSSH Signal Handling Vulnerability).

Upgrading eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at openssh.org. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published 3 years after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (29254), Tenable (23671), SecurityFocus (BID 20241†), OSVDB (29264†) and Secunia (SA22173†). See VDB-32699, VDB-32532, VDB-32512 and VDB-44077 for similar entries. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.3
VulDB Temp Score: 6.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Proof-of-Concept

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 23671
Nessus Name: GLSA-200611-06 : OpenSSH: Multiple Denial of Service vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍
Nessus Port: 🔍

OpenVAS ID: 57483
OpenVAS Name: Debian Security Advisory DSA 1189-1 (openssh-krb5)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
Exposure Time: 🔍

Patch: openssh.org

Timelineinfo

09/27/2006 🔍
09/27/2006 +0 days 🔍
09/27/2006 +0 days 🔍
09/27/2006 +0 days 🔍
09/28/2006 +1 days 🔍
09/29/2006 +1 days 🔍
09/29/2006 +0 days 🔍
09/29/2006 +0 days 🔍
10/01/2006 +1 days 🔍
10/02/2006 +1 days 🔍
11/20/2006 +49 days 🔍
09/12/2008 +662 days 🔍
09/16/2008 +4 days 🔍
12/17/2024 +5936 days 🔍

Sourcesinfo

Vendor: openbsd.org

Advisory: openssh.org
Researcher: Mark Dowd
Organization: ISS X-Force
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2006-5051 (🔍)
GCVE (CVE): GCVE-0-2006-5051
GCVE (VulDB): GCVE-100-2578

OVAL: 🔍
IAVM: 🔍

CERT: 🔍
X-Force: 29254 - OpenSSH signal handler race condition, Medium Risk
SecurityFocus: 20241 - Portable OpenSSH GSSAPI Remote Code Execution Vulnerability
Secunia: 22173 - OpenSSH Signal Handling Vulnerability and User Enumeration Weakness, Highly Critical
OSVDB: 29264 - OpenSSH Signal Handler Pre-authentication Race Condition Code Execution
SecurityTracker: 1016940
Vulnerability Center: 12799 - OpenSSH Signal Handler Race Condition Allows Remote DoS and Code Execution, Critical
Vupen: ADV-2006-4018

See also: 🔍

Entryinfo

Created: 10/02/2006 11:34
Updated: 12/17/2024 11:21
Changes: 10/02/2006 11:34 (108), 07/08/2019 21:02 (2), 07/01/2024 14:33 (28), 12/17/2024 11:21 (2)
Complete: 🔍
Cache ID: 216:457:103

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