Sicherheitslücken in dropbear

mkj Dropbear S Range Check curve25519.c unpackneg signature verification

A vulnerability was determined in mkj Dropbear up to 2025.89. Impacted is the function unpackneg of the file src/curve25519.c of the component S Range Check. This manipulation causes improper verification of cryptographic signature. The attack can be initiated remotely. The attack is considered to have high complexity. The exploitability is considered difficult. The actual existence of this vulnerability is currently in question. Patch name: fdec3c90a15447bd538641d85e5a3e3ac981011d. To fix this issue, it is recommended to deploy a patch. The project maintainer explains: "Signature Malleability is not exploitable in SSH protocol. (...) [A] PoC

Dropbear: privilege escalation via unix domain socket forwardings

A flaw was found in Dropbear. When running in multi-user mode and authenticating users, the dropbear ssh server does the socket forwardings requested by the remote client as root, only switching to the logged-in user upon spawning a shell or performing some operations like reading the user's files. With the recent ability of also using unix domain sockets as the forwarding destination any user able to log in via ssh can connect to any unix socket with the root's credentials, bypassing both file system restrictions and any SO_PEERCRED / SO_PASSCRED checks performed by the peer.

• Auf 2025.89-1~deb13u1 aktualisieren

dropbear - security update

dropbear - security update

• Auf 2025.89-1~deb13u1 aktualisieren

CVE-2025-47203

dbclient in Dropbear SSH before 2025.88 allows command injection via an untrusted hostname argument, because a shell is used.

• Auf 2025.88-1 aktualisieren

CVE-2023-48795

The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and mishandles use of sequence numbers. For example, there is an effective attack against SSH's use of ChaCha20-Poly1305 (and CBC with E

• Auf 2022.83-4 aktualisieren

CVE-2021-36369

An issue was discovered in Dropbear through 2020.81. Due to a non-RFC-compliant check of the available authentication methods in the client-side SSH code, it is possible for an SSH server to change the login process in its favor. This attack can bypass additional security measures such as FIDO2 tokens or SSH-Askpass. Thus, it allows an attacker to abuse a forwarded agent for logging on to another server unnoticed.

• Auf 2022.82-1 aktualisieren

CVE-2020-36254

scp.c in Dropbear before 2020.79 mishandles the filename of . or an empty filename, a related issue to CVE-2018-20685.

• Auf 2020.79-1 aktualisieren

CVE-2019-12953

Dropbear 2011.54 through 2018.76 has an inconsistent failure delay that may lead to revealing valid usernames, a different issue than CVE-2018-15599.

• Auf 2019.78-1 aktualisieren

CVE-2017-2659

It was found that dropbear before version 2013.59 with GSSAPI leaks whether given username is valid or invalid. When an invalid username is given, the GSSAPI authentication failure was incorrectly counted towards the maximum allowed number of password attempts.

• Auf 2013.60-1 aktualisieren

CVE-2018-15599

The recv_msg_userauth_request function in svr-auth.c in Dropbear through 2018.76 is prone to a user enumeration vulnerability because username validity affects how fields in SSH_MSG_USERAUTH messages are handled, a similar issue to CVE-2018-15473 in an unrelated codebase.

• Auf 2018.76-4 aktualisieren

CVE-2017-9079

Dropbear before 2017.75 might allow local users to read certain files as root, if the file has the authorized_keys file format with a command= option. This occurs because ~/.ssh/authorized_keys is read with root privileges and symlinks are followed.

• Auf 2016.74-5 aktualisieren

CVE-2017-9078

The server in Dropbear before 2017.75 might allow post-authentication root remote code execution because of a double free in cleanup of TCP listeners when the -a option is enabled.

• Auf 2016.74-5 aktualisieren

CVE-2016-7409

The dbclient and server in Dropbear SSH before 2016.74, when compiled with DEBUG_TRACE, allows local users to read process memory via the -v argument, related to a failed remote ident.

• Auf 2016.74-1 aktualisieren

CVE-2016-7408

The dbclient in Dropbear SSH before 2016.74 allows remote attackers to execute arbitrary code via a crafted (1) -m or (2) -c argument.

• Auf 2016.74-1 aktualisieren

CVE-2016-7407

The dropbearconvert command in Dropbear SSH before 2016.74 allows attackers to execute arbitrary code via a crafted OpenSSH key file.

• Auf 2016.74-1 aktualisieren

CVE-2016-7406

Format string vulnerability in Dropbear SSH before 2016.74 allows remote attackers to execute arbitrary code via format string specifiers in the (1) username or (2) host argument.

• Auf 2016.74-1 aktualisieren

CVE-2016-3116

CRLF injection vulnerability in Dropbear SSH before 2016.72 allows remote authenticated users to bypass intended shell-command restrictions via crafted X11 forwarding data.

• Auf 2016.72-1 aktualisieren

CVE-2013-4434

Dropbear SSH Server before 2013.59 generates error messages for a failed logon attempt with different time delays depending on whether the user account exists, which allows remote attackers to discover valid usernames.

• Auf 2012.55-1.4 aktualisieren

CVE-2013-4421

The buf_decompress function in packet.c in Dropbear SSH Server before 2013.59 allows remote attackers to cause a denial of service (memory consumption) via a compressed packet that has a large size when it is decompressed.

• Auf 2012.55-1.4 aktualisieren

CVE-2012-0920

Use-after-free vulnerability in Dropbear SSH Server 0.52 through 2012.54, when command restriction and public key authentication are enabled, allows remote authenticated users to execute arbitrary code and bypass command restrictions via multiple crafted command requests, related to "channels concurrency."

• Auf 2012.55-1 aktualisieren