
CVE-2021-20230 – stunnel: client certificate not correctly verified when redirect and verifyChain options are used
https://notcve.org/view.php?id=CVE-2021-20230
22 Feb 2021 — A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality. Se encontró un fallo en stunnel versiones a... • https://bugzilla.redhat.com/show_bug.cgi?id=1925226 • CWE-295: Improper Certificate Validation •

CVE-2014-0016 – Gentoo Linux Security Advisory 201408-14
https://notcve.org/view.php?id=CVE-2014-0016
23 Mar 2014 — stunnel before 5.00, when using fork threading, does not properly update the state of the OpenSSL pseudo-random number generator (PRNG), which causes subsequent children with the same process ID to use the same entropy pool and allows remote attackers to obtain private keys for EC (ECDSA) or DSA certificates. stunnel anterior a 5.00, cuando utilizando hilo de bifurcación, no actualiza debidamente el estado del generador de números psuedoaleatorios OpenSSL (PRNG), lo que causa que hijos posteriores con el mi... • http://www.openwall.com/lists/oss-security/2014/03/05/1 • CWE-332: Insufficient Entropy in PRNG •

CVE-2013-1762 – Stunnel: buffer overflow vulnerability due to incorrect integer conversion in the NTLM authentication of the CONNECT protocol negotiation
https://notcve.org/view.php?id=CVE-2013-1762
08 Mar 2013 — stunnel 4.21 through 4.54, when CONNECT protocol negotiation and NTLM authentication are enabled, does not correctly perform integer conversion, which allows remote proxy servers to execute arbitrary code via a crafted request that triggers a buffer overflow. stunnel v4.21 a v4.54, cuando el protocolo de negociación CONNECT y la autenticación NTLM están habilitadas, no realiza la conversión de enteros correctamente, lo que permite ejecutar código de su elección a servidores remotos proxy a través de una sol... • http://rhn.redhat.com/errata/RHSA-2013-0714.html • CWE-94: Improper Control of Generation of Code ('Code Injection') •

CVE-2008-2400
https://notcve.org/view.php?id=CVE-2008-2400
22 May 2008 — Unspecified vulnerability in stunnel before 4.23, when running as a service on Windows, allows local users to gain privileges via unknown attack vectors. Vulnerabilidad sin especificar en stunnel anterior a 4.23, cuando es ejecutado como un servicio en Windows, permite a usuarios locales obtener privilegios a través de vectores de ataque desconocidos. • http://secunia.com/advisories/30297 • CWE-264: Permissions, Privileges, and Access Controls •

CVE-2003-0740 – Stunnel 3.24/4.00 - Daemon Hijacking
https://notcve.org/view.php?id=CVE-2003-0740
04 Sep 2003 — Stunnel 4.00, and 3.24 and earlier, leaks a privileged file descriptor returned by listen(), which allows local users to hijack the Stunnel server. • https://www.exploit-db.com/exploits/91 •

CVE-2002-0002 – STunnel 3.x - Client Negotiation Protocol Format String
https://notcve.org/view.php?id=CVE-2002-0002
31 Jan 2002 — Format string vulnerability in stunnel before 3.22 when used in client mode for (1) smtp, (2) pop, or (3) nntp allows remote malicious servers to execute arbitrary code. Vulnerabilidad en el formateado de cadenas en stunnel anterior a la 3.22 cuando se usa en modo cliente para smtp, pop o nntp permite que servidores remotos maliciosos ejecuten código arbitrario. • https://www.exploit-db.com/exploits/21192 •

CVE-2001-0060
https://notcve.org/view.php?id=CVE-2001-0060
12 Feb 2001 — Format string vulnerability in stunnel 3.8 and earlier allows attackers to execute arbitrary commands via a malformed ident username. • http://archives.neohapsis.com/archives/bugtraq/2000-12/0337.html •