Debian OpenSSH vulnerabilities

CVE-2023-25136 [MEDIUM] CVE-2023-25136: openssh - OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.... OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible

CVE-2021-41617 [HIGH] CVE-2021-41617: openssh - sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurati... sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used, allows privilege escalation because supplemental groups are not initialized as expected. Helper programs for AuthorizedKeysCommand and AuthorizedPrincipalsCommand may run with privileges associated with group memberships of the sshd process, if the configuration specifies r

CVE-2021-28041 [HIGH] CVE-2021-28041: openssh - ssh-agent in OpenSSH before 8.5 has a double free that may be relevant in a few ... ssh-agent in OpenSSH before 8.5 has a double free that may be relevant in a few less-common scenarios, such as unconstrained agent-socket access on a legacy operating system, or the forwarding of an agent to an attacker-controlled host. Scope: local bookworm: resolved (fixed in 1:8.4p1-5) bullseye: resolved (fixed in 1:8.4p1-5) forky: resolved (fixed in 1:8.4p1-5) s

CVE-2021-36368 [LOW] CVE-2021-36368: openssh - An issue was discovered in OpenSSH before 8.9. If a client is using public-key a... An issue was discovered in OpenSSH before 8.9. If a client is using public-key authentication with agent forwarding but without -oLogLevel=verbose, and an attacker has silently modified the server to support the None authentication option, then the user cannot determine whether FIDO authentication is going to confirm that the user wishes to connect to that server, or

CVE-2020-14145 [MEDIUM] CVE-2020-14145: openssh - The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy leading... The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy leading to an information leak in the algorithm negotiation. This allows man-in-the-middle attackers to target initial connection attempts (where no host key for the server has been cached by the client). NOTE: some reports state that 8.5 and 8.6 are also affected. Scope: local bookworm: open

CVE-2020-12062 [HIGH] CVE-2020-12062: openssh - The scp client in OpenSSH 8.2 incorrectly sends duplicate responses to the serve... 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 fil

CVE-2020-15778 [HIGH] CVE-2020-15778: openssh - scp in OpenSSH through 8.3p1 allows command injection in the scp.c toremote func... scp in OpenSSH through 8.3p1 allows command injection in the scp.c toremote function, as demonstrated by backtick characters in the destination argument. NOTE: the vendor reportedly has stated that they intentionally omit validation of "anomalous argument transfers" because that could "stand a great chance of breaking existing workflows." Scope: local bookworm: open

CVE-2019-6109 [MEDIUM] CVE-2019-6109: openssh - An issue was discovered in OpenSSH 7.9. Due to missing character encoding in the... 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. Scope: local book

CVE-2019-6111 [MEDIUM] CVE-2019-6111: openssh - An issue was discovered in OpenSSH 7.9. Due to the scp implementation being deri... 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 overwrit

CVE-2019-6110 [MEDIUM] CVE-2019-6110: openssh - In OpenSSH 7.9, due to accepting and displaying arbitrary stderr output from the... In OpenSSH 7.9, due to accepting and displaying arbitrary stderr output from the server, a malicious server (or Man-in-The-Middle attacker) can manipulate the client output, for example to use ANSI control codes to hide additional files being transferred. Scope: local bookworm: open bullseye: open forky: open sid: open trixie: open

CVE-2019-16905 [HIGH] CVE-2019-16905: openssh - OpenSSH 7.7 through 7.9 and 8.x before 8.1, when compiled with an experimental k... OpenSSH 7.7 through 7.9 and 8.x before 8.1, when compiled with an experimental key type, has a pre-authentication integer overflow if a client or server is configured to use a crafted XMSS key. This leads to memory corruption and local code execution because of an error in the XMSS key parsing algorithm. NOTE: the XMSS implementation is considered experimental in al

CVE-2018-15473 [MEDIUM] CVE-2018-15473: openssh - OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not dela... OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not delaying bailout for an invalid authenticating user until after the packet containing the request has been fully parsed, related to auth2-gss.c, auth2-hostbased.c, and auth2-pubkey.c. Scope: local bookworm: resolved (fixed in 1:7.7p1-4) bullseye: resolved (fixed in 1:7.7p1-4) forky: resolv

CVE-2018-20685 [MEDIUM] CVE-2018-20685: openssh - In OpenSSH 7.9, scp.c in the scp client allows remote SSH servers to bypass inte... 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. Scope: local bookworm: resolved (fixed in 1:7.9p1-5) bullseye: resolved (fixed in 1:7.9p1-5) forky: resolved (fixed in 1:7.9p1-5) sid

CVE-2018-15919 [MEDIUM] CVE-2018-15919: openssh - Remotely observable behaviour in auth-gss2.c in OpenSSH through 7.8 could be use... Remotely observable behaviour in auth-gss2.c in OpenSSH through 7.8 could be used by remote attackers to detect existence of users on a target system when GSS2 is in use. NOTE: the discoverer states 'We understand that the OpenSSH developers do not want to treat such a username enumeration (or "oracle") as a vulnerability.' Scope: local bookworm: open bullseye: op

CVE-2017-15906 [MEDIUM] CVE-2017-15906: openssh - The process_open function in sftp-server.c in OpenSSH before 7.6 does not proper... The process_open function in sftp-server.c in OpenSSH before 7.6 does not properly prevent write operations in readonly mode, which allows attackers to create zero-length files. Scope: local bookworm: resolved (fixed in 1:7.6p1-1) bullseye: resolved (fixed in 1:7.6p1-1) forky: resolved (fixed in 1:7.6p1-1) sid: resolved (fixed in 1:7.6p1-1) trixie: resolved (fixed

CVE-2016-1908 [CRITICAL] CVE-2016-1908: openssh - The client in OpenSSH before 7.2 mishandles failed cookie generation for untrust... The client in OpenSSH before 7.2 mishandles failed cookie generation for untrusted X11 forwarding and relies on the local X11 server for access-control decisions, which allows remote X11 clients to trigger a fallback and obtain trusted X11 forwarding privileges by leveraging configuration issues on this X11 server, as demonstrated by lack of the SECURITY extension

CVE-2016-0778 [HIGH] CVE-2016-0778: openssh - The (1) roaming_read and (2) roaming_write functions in roaming_common.c in the ... The (1) roaming_read and (2) roaming_write functions in roaming_common.c in the client in OpenSSH 5.x, 6.x, and 7.x before 7.1p2, when certain proxy and forward options are enabled, do not properly maintain connection file descriptors, which allows remote servers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact by req

CVE-2016-6515 [HIGH] CVE-2016-6515: openssh - The auth_password function in auth-passwd.c in sshd in OpenSSH before 7.3 does n... The auth_password function in auth-passwd.c in sshd in OpenSSH before 7.3 does not limit password lengths for password authentication, which allows remote attackers to cause a denial of service (crypt CPU consumption) via a long string. Scope: local bookworm: resolved (fixed in 1:7.3p1-1) bullseye: resolved (fixed in 1:7.3p1-1) forky: resolved (fixed in 1:7.3p1-1) sid

CVE-2016-10708 [HIGH] CVE-2016-10708: openssh - sshd in OpenSSH before 7.4 allows remote attackers to cause a denial of service ... sshd in OpenSSH before 7.4 allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via an out-of-sequence NEWKEYS message, as demonstrated by Honggfuzz, related to kex.c and packet.c. Scope: local bookworm: resolved (fixed in 1:7.4p1-1) bullseye: resolved (fixed in 1:7.4p1-1) forky: resolved (fixed in 1:7.4p1-1) sid: resolved

CVE-2016-8858 [HIGH] CVE-2016-8858: openssh - The kex_input_kexinit function in kex.c in OpenSSH 6.x and 7.x through 7.3 allow... The kex_input_kexinit function in kex.c in OpenSSH 6.x and 7.x through 7.3 allows remote attackers to cause a denial of service (memory consumption) by sending many duplicate KEXINIT requests. NOTE: a third party reports that "OpenSSH upstream does not consider this as a security issue." Scope: local bookworm: resolved (fixed in 1:7.3p1-2) bullseye: resolved (fixed in