CVE-2020-12062
https://notcve.org/view.php?id=CVE-2020-12062
The scp client in OpenSSH 8.2 incorrectly sends duplicate responses to the server upon a utimes system call failure, which allows a malicious unprivileged user on the remote server to overwrite arbitrary files in the client's download directory by creating a crafted subdirectory anywhere on the remote server. The victim must use the command scp -rp to download a file hierarchy containing, anywhere inside, this crafted subdirectory. NOTE: the vendor points out that "this attack can achieve no more than a hostile peer is already able to achieve within the scp protocol" and "utimes does not fail under normal circumstances. ** EN DISPUTA** El cliente scp en OpenSSH versión 8.2 envía incorrectamente respuestas duplicadas al servidor tras un fallo en la llamada de sistema utimes, lo que permite a un usuario malicioso sin privilegios en el servidor remoto sobrescribir archivos arbitrarios en el directorio de descarga del cliente mediante la creación de un subdirectorio diseñado en cualquier lugar del servidor remoto. La víctima debe usar el comando scp -rp para descargar una jerarquía de archivos que contenga, en cualquier lugar de su interior, este subdirectorio creado. NOTA: el vendedor señala que "este ataque no puede lograr más de lo que un peer hostil ya se puede lograr dentro del protocolo scp" y "utimes no presenta un fallo bajo circunstancias normales". • https://github.com/openssh/openssh-portable/commit/955854cafca88e0cdcd3d09ca1ad4ada465364a1 https://github.com/openssh/openssh-portable/commit/aad87b88fc2536b1ea023213729aaf4eaabe1894 https://www.openssh.com/txt/release-8.3 https://www.openwall.com/lists/oss-security/2020/05/27/1 • CWE-20: Improper Input Validation •
CVE-2019-6111 – OpenSSH SCP Client - Write Arbitrary Files
https://notcve.org/view.php?id=CVE-2019-6111
An issue was discovered in OpenSSH 7.9. Due to the scp implementation being derived from 1983 rcp, the server chooses which files/directories are sent to the client. However, the scp client only performs cursory validation of the object name returned (only directory traversal attacks are prevented). A malicious scp server (or Man-in-The-Middle attacker) can overwrite arbitrary files in the scp client target directory. If recursive operation (-r) is performed, the server can manipulate subdirectories as well (for example, to overwrite the .ssh/authorized_keys file). • https://www.exploit-db.com/exploits/46516 https://www.exploit-db.com/exploits/46193 http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00058.html http://www.openwall.com/lists/oss-security/2019/04/18/1 http://www.openwall.com/lists/oss-security/2022/08/02/1 http://www.securityfocus.com/bid/106741 https://access.redhat.com/errata/RHSA-2019:3702 https://bugzilla.redhat.com/show_bug.cgi?id=1677794 https://cert-portal.siemens.com/productcert/pdf/ssa-412672 • CWE-20: Improper Input Validation CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') •
CVE-2019-6109 – openssh: Missing character encoding in progress display allows for spoofing of scp client output
https://notcve.org/view.php?id=CVE-2019-6109
An issue was discovered in OpenSSH 7.9. Due to missing character encoding in the progress display, a malicious server (or Man-in-The-Middle attacker) can employ crafted object names to manipulate the client output, e.g., by using ANSI control codes to hide additional files being transferred. This affects refresh_progress_meter() in progressmeter.c. Se ha descubierto un problema en OpenSSH 7.9. Debido a la falta de cifrado de caracteres en la pantalla de progreso, un servidor malicioso (o atacante Man-in-the-Middle) puede emplear nombres de objeto manipulados para manipular la salida del cliente, por ejemplo, empleando códigos de control de ANSI para ocultar los archivos adicionales que se están transfiriendo. • http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00058.html https://access.redhat.com/errata/RHSA-2019:3702 https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf https://cvsweb.openbsd.org/src/usr.bin/ssh/progressmeter.c https://cvsweb.openbsd.org/src/usr.bin/ssh/scp.c https://lists.debian.org/debian-lts-announce/2019/03/msg00030.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W3YVQ2BPTOVDCFDVNC2GGF5P5ISFG37G https:// • CWE-116: Improper Encoding or Escaping of Output CWE-451: User Interface (UI) Misrepresentation of Critical Information •
CVE-2018-20685 – openssh: scp client improper directory name validation
https://notcve.org/view.php?id=CVE-2018-20685
In OpenSSH 7.9, scp.c in the scp client allows remote SSH servers to bypass intended access restrictions via the filename of . or an empty filename. The impact is modifying the permissions of the target directory on the client side. En OpenSSH 7.9, scp.c en el cliente scp permite que los servidores SSH omitan las restricciones de acceso planeadas mediante un nombre de archivo "." o un nombre de archivo vacío. El impacto consiste en modificar los permisos del directorio objetivo en el lado del cliente. • http://www.securityfocus.com/bid/106531 https://access.redhat.com/errata/RHSA-2019:3702 https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/scp.c.diff?r1=1.197&r2=1.198&f=h https://github.com/openssh/openssh-portable/commit/6010c0303a422a9c5fa8860c061bf7105eb7f8b2 https://lists.debian.org/debian-lts-announce/2019/03/msg00030.html https://security.gentoo.org/glsa/201903-16 https://security.gentoo.org/glsa/202007- • CWE-20: Improper Input Validation CWE-863: Incorrect Authorization •