Vulnerability Report

CVE-2002-1336

Title: TightVNC predictable challenge string allows authentication bypass

Other

Proof Of Concept

No public PoC currently indexed for CVE-2002-1336.

CWE Category NVD-CWE-noinfo

Published Date Dec 11, 2002

Modified Date Jun 16, 2026

Exploit Status Not Found

Score 7.5 CVSS v2.0

Exploit Probability (EPSS)

2.40%

Vulnerability Summary

CVE-2002-1336: 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.

Impacted Vendors

tightvnc 1

Reference Links

http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000640 http://marc.info/?l=bugtraq&m=102753170201524&w=2 http://marc.info/?l=bugtraq&m=102769183913594&w=2 http://www.mandrakesoft.com/security/advisories?name=MDKSA-2003:022 http://www.redhat.com/support/errata/RHSA-2002-287.html http://www.redhat.com/support/errata/RHSA-2003-041.html http://www.securityfocus.com/bid/5296 http://www.tightvnc.com/WhatsNew.txt https://exchange.xforce.ibmcloud.com/vulnerabilities/5992 http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000640 http://marc.info/?l=bugtraq&m=102753170201524&w=2 http://marc.info/?l=bugtraq&m=102769183913594&w=2 http://www.mandrakesoft.com/security/advisories?name=MDKSA-2003:022 http://www.redhat.com/support/errata/RHSA-2002-287.html http://www.redhat.com/support/errata/RHSA-2003-041.html http://www.securityfocus.com/bid/5296 http://www.tightvnc.com/WhatsNew.txt https://exchange.xforce.ibmcloud.com/vulnerabilities/5992

CVSS v2.0

Source Entity [email protected]

Severity HIGH

7.5

Access Vector

N/A

Authentication

N/A

RAW VECTOR AV:N/AC:L/Au:N/C:P/I:P/A:P

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2002-1336 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

June 16, 2026 MODIFIED

Vulnerability data updated via NVD.

April 03, 2025 MODIFIED

Vulnerability data or affected products updated.

December 11, 2002 PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector N/A

Complexity N/A

Privileges N/A

Interaction NONE

CVSS Vector String


                                    AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected Stack

No specific products linked.