TightVNC up to 1.2.5 Authentication missing encryption

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability was found in TightVNC 1.2.0/1.2.1/1.2.3/1.2.4/1.2.5. It has been rated as problematic. This impacts an unknown function of the component Authentication. Performing a manipulation results in missing encryption. This vulnerability is known as CVE-2002-1336. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in TightVNC 1.2.0/1.2.1/1.2.3/1.2.4/1.2.5. This affects an unknown function of the component Authentication. The manipulation with an unknown input leads to a missing encryption vulnerability. CWE is classifying the issue as CWE-311. The product does not encrypt sensitive or critical information before storage or transmission. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

TightVNC before 1.2.6 generates the same challenge string for multiple connections, which allows remote attackers to bypass VNC authentication by sniffing the challenge and response of other users.

The weakness was published 12/11/2002 (Website). It is possible to read the advisory at xforce.iss.net. This vulnerability is uniquely identified as CVE-2002-1336. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1600 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 14007 (Mandrake Linux Security Advisory : vnc (MDKSA-2003:022)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Mandriva Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 38363 (Red Hat VNC Repeated Challenge Replay Attack Vulnerability).

Upgrading to version 1.2.6 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 X-Force (5992), Tenable (14007), SecurityFocus (BID 5296†) and Vulnerability Center (SBV-4940†). Similar entry is available at VDB-16359. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Missing encryption
CWE: CWE-311 / CWE-310
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 14007
Nessus Name: Mandrake Linux Security Advisory : vnc (MDKSA-2003:022)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍
Nessus Port: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: TightVNC 1.2.6

Timelineinfo

07/24/2002 🔍
12/11/2002 +140 days 🔍
12/11/2002 +0 days 🔍
12/11/2002 +0 days 🔍
02/24/2003 +75 days 🔍
07/31/2004 +523 days 🔍
08/03/2004 +3 days 🔍
07/31/2014 +3649 days 🔍
09/06/2025 +4055 days 🔍

Sourcesinfo

Advisory: xforce.iss.net
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2002-1336 (🔍)
GCVE (CVE): GCVE-0-2002-1336
GCVE (VulDB): GCVE-100-19215
X-Force: 5992
SecurityFocus: 5296 - TightVNC Repeated Challenge Replay Attack Vulnerability
Vulnerability Center: 4940 - VNC Weak User Authentication due to Same Challenge String for Multiple Connections, High

See also: 🔍

Entryinfo

Created: 07/31/2014 17:11
Updated: 09/06/2025 18:56
Changes: 07/31/2014 17:11 (68), 05/23/2019 17:25 (2), 09/06/2025 18:56 (20)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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