CVE-2021-3738
https://notcve.org/view.php?id=CVE-2021-3738
In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called 'association groups'. These handles can reference connections to our sam.ldb database. However while the database was correctly shared, the user credentials state was only pointed at, and when one connection within that association group ended, the database would be left pointing at an invalid 'struct session_info'. The most likely outcome here is a crash, but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access. En DCE/RPC es posible compartir los manejadores (cookies para el estado de los recursos) entre múltiples conexiones por medio de un mecanismo llamado "association groups". • https://bugzilla.redhat.com/show_bug.cgi?id=2021726 https://bugzilla.samba.org/show_bug.cgi?id=14468 https://security.gentoo.org/glsa/202309-06 https://www.samba.org/samba/security/CVE-2021-3738.html • CWE-416: Use After Free •
CVE-2020-25722
https://notcve.org/view.php?id=CVE-2020-25722
Multiple flaws were found in the way samba AD DC implemented access and conformance checking of stored data. An attacker could use this flaw to cause total domain compromise. Se han encontrado múltiples fallos en la forma en que samba AD DC implementa el acceso y la comprobación de conformidad de los datos almacenados. Un atacante podría usar este fallo para causar un compromiso total del dominio • https://bugzilla.redhat.com/show_bug.cgi?id=2019764 https://security.gentoo.org/glsa/202309-06 https://www.samba.org/samba/security/CVE-2020-25722.html • CWE-863: Incorrect Authorization •
CVE-2021-23192 – samba: Subsequent DCE/RPC fragment injection vulnerability
https://notcve.org/view.php?id=CVE-2021-23192
A flaw was found in the way samba implemented DCE/RPC. If a client to a Samba server sent a very large DCE/RPC request, and chose to fragment it, an attacker could replace later fragments with their own data, bypassing the signature requirements. Se ha encontrado un fallo en la forma en que samba implementa DCE/RPC. Si un cliente a un servidor Samba enviaba una petición DCE/RPC muy grande, y elegía fragmentarla, un atacante podía reemplazar los fragmentos posteriores con sus propios datos, omitiendo los requisitos de firma A flaw was found in the way samba implemented DCE/RPC. If a client to a Samba server sent a very large DCE/RPC request, and chose to fragment it, an attacker could replace later fragments with their own data, bypassing the signature requirements. • https://bugzilla.redhat.com/show_bug.cgi?id=2019666 https://security.gentoo.org/glsa/202309-06 https://ubuntu.com/security/CVE-2021-23192 https://www.samba.org/samba/security/CVE-2021-23192.html https://access.redhat.com/security/cve/CVE-2021-23192 • CWE-20: Improper Input Validation •
CVE-2020-17049 – Kerberos KDC Security Feature Bypass Vulnerability
https://notcve.org/view.php?id=CVE-2020-17049
<p>A security feature bypass vulnerability exists in the way Key Distribution Center (KDC) determines if a service ticket can be used for delegation via Kerberos Constrained Delegation (KCD).</p> <p>To exploit the vulnerability, a compromised service that is configured to use KCD could tamper with a service ticket that is not valid for delegation to force the KDC to accept it.</p> <p>The update addresses this vulnerability by changing how the KDC validates service tickets used with KCD.</p> Vulnerabilidad de Omisión de la Característica de Seguridad de Kerberos A security feature bypass vulnerability exists in the way Key Distribution Center (KDC) determines if a service ticket can be used for delegation via Kerberos Constrained Delegation (KCD). To exploit the vulnerability, a compromised service that is configured to use KCD could tamper with a service ticket that is not valid for delegation to force the KDC to accept it. The update addresses this vulnerability by changing how the KDC validates service tickets used with KCD. It was found that the Kerberos Key Distribution Center (KDC) delegation feature, Service for User (S4U), did not sufficiently protect the tickets it's providing from tempering. • http://www.openwall.com/lists/oss-security/2021/11/10/3 https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17049 https://security.gentoo.org/glsa/202309-06 https://access.redhat.com/security/cve/CVE-2020-17049 https://bugzilla.redhat.com/show_bug.cgi?id=2025721 • CWE-345: Insufficient Verification of Data Authenticity CWE-863: Incorrect Authorization •