Snort 2.4.3 frag3 Preprocessor ip_option_length security check

CVSS Meta Temp Score
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CTI Interest Score
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4.6$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Snort 2.4.3. This impacts an unknown function of the component frag3 Preprocessor. Such manipulation of the argument ip_option_length leads to security check. This vulnerability is documented as CVE-2006-0839. The attack can be executed remotely. There is not any exploit available. Restrictive firewalling should be applied.

Detailsinfo

A vulnerability was found in Snort 2.4.3 and classified as critical. Affected by this issue is an unknown functionality of the component frag3 Preprocessor. The manipulation of the argument ip_option_length with an unknown input leads to a security check vulnerability. Using CWE to declare the problem leads to CWE-358. The product does not implement or incorrectly implements one or more security-relevant checks as specified by the design of a standardized algorithm, protocol, or technique. Impacted is integrity. CVE summarizes:

The frag3 preprocessor in Sourcefire Snort 2.4.3 does not properly reassemble certain fragmented packets with IP options, which allows remote attackers to evade detection of certain attacks, possibly related to IP option lengths.

The weakness was released 02/27/2006 by siouxsie as confirmed posting (Bugtraq). The advisory is available at securityfocus.com. This vulnerability is handled as CVE-2006-0839 since 02/22/2006. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1211 by the MITRE ATT&CK project.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 34043 (Snort Frag3 Processor Fragmented Packet Detection Evasion Vulnerability).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at snort.org.Addressing this vulnerability is possible by firewalling . The best possible mitigation is suggested to be applying a restrictive firewalling. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 12437.

The vulnerability is also documented in the databases at X-Force (24811), SecurityFocus (BID 16705†), OSVDB (23501†), Secunia (SA18959†) and Vulnerability Center (SBV-10987†). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.6

VulDB Base Score: 5.3
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Security check
CWE: CWE-358
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Firewall
Status: 🔍
Patch: snort.org
TippingPoint: 🔍

McAfee IPS: 🔍
McAfee IPS Version: 🔍

ISS Proventia IPS: 🔍

Timelineinfo

02/17/2006 🔍
02/17/2006 +0 days 🔍
02/21/2006 +4 days 🔍
02/21/2006 +0 days 🔍
02/22/2006 +0 days 🔍
02/27/2006 +5 days 🔍
03/03/2006 +4 days 🔍
04/10/2006 +38 days 🔍
06/22/2025 +7013 days 🔍

Sourcesinfo

Advisory: securityfocus.com⛔
Researcher: siouxsie
Status: Confirmed

CVE: CVE-2006-0839 (🔍)
GCVE (CVE): GCVE-0-2006-0839
GCVE (VulDB): GCVE-100-2066
X-Force: 24811 - Snort frag3 preprocessor IDS detection bypass, Medium Risk
SecurityFocus: 16705 - Snort Frag3 Processor Fragmented Packet Detection Evasion Vulnerability
Secunia: 18959 - Snort frag3 Preprocessor Packet Reassembly Vulnerability, Moderately Critical
OSVDB: 23501 - Snort frag3 Processor Crafted IP Options Packet Detection Bypass
Vulnerability Center: 10987 - Snort Detection Bypass via frag3 Preprocessor, Medium

Entryinfo

Created: 03/03/2006 15:15
Updated: 06/22/2025 22:23
Changes: 03/03/2006 15:15 (71), 06/07/2017 16:04 (10), 06/22/2025 22:23 (21)
Complete: 🔍
Cache ID: 216:7BF:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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