OpenBSD up to 3.6 TCP Connection Timestamp denial of service

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in OpenBSD up to 3.6. This affects an unknown function of the component TCP Connection Timestamp Handler. The manipulation leads to denial of service. This vulnerability is listed as CVE-2005-0356. The attack may be initiated remotely. In addition, an exploit is available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in OpenBSD up to 3.6 (Operating System). It has been rated as critical. This issue affects some unknown functionality of the component TCP Connection Timestamp Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

Multiple TCP implementations with Protection Against Wrapped Sequence Numbers (PAWS) with the timestamps option enabled allow remote attackers to cause a denial of service (connection loss) via a spoofed packet with a large timer value, which causes the host to discard later packets because they appear to be too old.

The bug was discovered 05/18/2005. The weakness was presented 05/19/2005 by Noritoshi Demizu with US-CERT (Website). The advisory is shared at openbsd.org. The identification of this vulnerability is CVE-2005-0356 since 02/11/2005. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are unknown but a public exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

After 2 days, there has been an exploit disclosed. The exploit is available at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 78204 (F5 Networks BIG-IP : Inadequate validation for TCP segments (SOL4743)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family F5 Networks Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 90249 (Microsoft Windows TCP Reset Through Arbitrary Timer Value).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at ftp.openbsd.org. 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 (20635), Exploit-DB (1008), Tenable (78204), SecurityFocus (BID 13676†) and OSVDB (16685†). secunia.com is providing further details. See VDB-1489, VDB-1490, VDB-1491 and VDB-1535 for similar entries. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.8

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

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

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Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 78204
Nessus Name: F5 Networks BIG-IP : Inadequate validation for TCP segments (SOL4743)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍
Nessus Port: 🔍

OpenVAS ID: 53976
OpenVAS Name: FreeBSD Security Advisory (FreeBSD-SA-05:15.tcp.asc)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
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Patch: ftp.openbsd.org

Timelineinfo

02/11/2005 🔍
05/18/2005 +96 days 🔍
05/18/2005 +0 days 🔍
05/18/2005 +0 days 🔍
05/19/2005 +1 days 🔍
05/19/2005 +0 days 🔍
05/21/2005 +1 days 🔍
05/30/2005 +9 days 🔍
05/31/2005 +1 days 🔍
05/16/2007 +715 days 🔍
10/10/2014 +2704 days 🔍
07/05/2025 +3921 days 🔍

Sourcesinfo

Advisory: openbsd.org
Researcher: Noritoshi Demizu
Organization: US-CERT
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2005-0356 (🔍)
GCVE (CVE): GCVE-0-2005-0356
GCVE (VulDB): GCVE-100-1493
CERT: 🔍
X-Force: 20635 - TCP/IP timestamp denial of service, Medium Risk
SecurityFocus: 13676 - Multiple Vendor TCP Timestamp PAWS Remote Denial Of Service Vulnerability
Secunia: 15417 - OpenBSD TCP Timestamp Denial of Service, Less Critical
OSVDB: 16685 - Multiple Vendor Malformed TCP Timestamp DoS
SecurityTracker: 1014001
Vulnerability Center: 8039

scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍
See also: 🔍

Entryinfo

Created: 05/30/2005 14:51
Updated: 07/05/2025 15:42
Changes: 05/30/2005 14:51 (93), 07/03/2019 09:15 (8), 06/13/2024 10:57 (17), 01/23/2025 17:09 (1), 07/05/2025 15:42 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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