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 Encrypt-then-MAC). The bypass occurs in [email protected] and (if CBC is used) the [email protected] MAC algorithms. This also affects Maverick Synergy Java SSH API before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, PuTTY before 0.80, AsyncSSH before 2.14.2, golang.org/x/crypto before 0.17.0, libssh before 0.10.6, libssh2 through 1.11.0, Thorn Tech SFTP Gateway before 3.4.6, Tera Term before 5.1, Paramiko before 3.4.0, jsch before 0.2.15, SFTPGo before 2.5.6, Netgate pfSense Plus through 23.09.1, Netgate pfSense CE through 2.7.2, HPN-SSH through 18.2.0, ProFTPD before 1.3.8b (and before 1.3.9rc2), ORYX CycloneSSH before 2.3.4, NetSarang XShell 7 before Build 0144, CrushFTP before 10.6.0, ConnectBot SSH library before 2.2.22, Apache MINA sshd through 2.11.0, sshj through 0.37.0, TinySSH through 20230101, trilead-ssh2 6401, LANCOM LCOS and LANconfig, FileZilla before 3.66.4, Nova before 11.8, PKIX-SSH before 14.4, SecureCRT before 9.4.3, Transmit5 before 5.10.4, Win32-OpenSSH before 9.5.0.0p1-Beta, WinSCP before 6.2.2, Bitvise SSH Server before 9.32, Bitvise SSH Client before 9.33, KiTTY through 0.76.1.13, the net-ssh gem 7.2.0 for Ruby, the mscdex ssh2 module before 1.15.0 for Node.js, the thrussh library before 0.35.1 for Rust, and the Russh crate before 0.40.2 for Rust.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.9, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts integrity (unauthorized modifications), for affected systems. Impacting 68 products from openbsd, from putty, from filezilla-project and 65 others, organizations running these solutions should prioritize assessment and patching.
Reported in 2023, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2023-12-18T16:15:10.897
2025-11-04T22:15:55.110
Modified
CVSSv3.1: 5.9 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | openbsd | openssh | < 9.6 | Yes |
| Application | putty | putty | < 0.80 | Yes |
| Application | filezilla-project | filezilla_client | < 3.66.4 | Yes |
| Operating System | apple | macos | - | No |
| Application | panic | transmit_5 | < 5.10.4 | Yes |
| Operating System | apple | macos | - | No |
| Application | panic | nova | < 11.8 | Yes |
| Application | roumenpetrov | pkixssh | < 14.4 | Yes |
| Application | winscp | winscp | < 6.2.2 | Yes |
| Application | bitvise | ssh_client | < 9.33 | Yes |
| Application | bitvise | ssh_server | < 9.32 | Yes |
| Operating System | lancom-systems | lcos | ≤ 3.66.4 | Yes |
| Operating System | lancom-systems | lcos_fx | - | Yes |
| Operating System | lancom-systems | lcos_lx | - | Yes |
| Operating System | lancom-systems | lcos_sx | 4.20 | Yes |
| Operating System | lancom-systems | lcos_sx | 5.20 | Yes |
| Operating System | lancom-systems | lanconfig | - | Yes |
| Application | vandyke | securecrt | < 9.4.3 | Yes |
| Application | libssh | libssh | < 0.10.6 | Yes |
| Application | net-ssh | net-ssh | 7.2.0 | Yes |
| Application | ssh2_project | ssh2 | ≤ 1.11.0 | Yes |
| Application | proftpd | proftpd | ≤ 1.3.8b | Yes |
| Operating System | freebsd | freebsd | ≤ 12.4 | Yes |
| Application | crates | thrussh | < 0.35.1 | Yes |
| Application | tera_term_project | tera_term | ≤ 5.1 | Yes |
| Application | oryx-embedded | cyclone_ssh | < 2.3.4 | Yes |
| Application | crushftp | crushftp | ≤ 10.6.0 | Yes |
| Application | netsarang | xshell_7 | < build__0144 | Yes |
| Application | paramiko | paramiko | < 3.4.0 | Yes |
| Application | redhat | openshift_container_platform | 4.0 | Yes |
| Application | redhat | openstack_platform | 16.1 | Yes |
| Application | redhat | openstack_platform | 16.2 | Yes |
| Application | redhat | openstack_platform | 17.1 | Yes |
| Application | redhat | ceph_storage | 6.0 | Yes |
| Operating System | redhat | enterprise_linux | 8.0 | Yes |
| Operating System | redhat | enterprise_linux | 9.0 | Yes |
| Application | redhat | openshift_serverless | - | Yes |
| Application | redhat | openshift_gitops | - | Yes |
| Application | redhat | openshift_pipelines | - | Yes |
| Application | redhat | openshift_developer_tools_and_services | - | Yes |
| Application | redhat | openshift_data_foundation | 4.0 | Yes |
| Application | redhat | openshift_api_for_data_protection | - | Yes |
| Application | redhat | openshift_virtualization | 4 | Yes |
| Application | redhat | storage | 3.0 | Yes |
| Application | redhat | discovery | - | Yes |
| Application | redhat | openshift_dev_spaces | - | Yes |
| Application | redhat | cert-manager_operator_for_red_hat_openshift | - | Yes |
| Application | redhat | keycloak | - | Yes |
| Application | redhat | jboss_enterprise_application_platform | 7.0 | Yes |
| Application | redhat | single_sign-on | 7.0 | Yes |
| Application | redhat | advanced_cluster_security | 3.0 | Yes |
| Application | redhat | advanced_cluster_security | 4.0 | Yes |
| Application | golang | crypto | < 0.17.0 | Yes |
| Application | russh_project | russh | < 0.40.2 | Yes |
| Application | sftpgo_project | sftpgo | < 2.5.6 | Yes |
| Application | erlang | erlang\/otp | < 22.3.4.27 | Yes |
| Application | erlang | erlang\/otp | < 23.3.4.20 | Yes |
| Application | erlang | erlang\/otp | < 24.3.4.15 | Yes |
| Application | erlang | erlang\/otp | < 25.3.2.8 | Yes |
| Application | erlang | erlang\/otp | < 26.2.1 | Yes |
| Application | matez | jsch | < 0.2.15 | Yes |
| Application | libssh2 | libssh2 | < 1.11.1 | Yes |
| Application | asyncssh_project | asyncssh | < 2.14.2 | Yes |
| Application | dropbear_ssh_project | dropbear_ssh | < 2022.83 | Yes |
| Application | jadaptive | maverick_synergy_java_ssh_api | < 3.1.0-snapshot | Yes |
| Application | ssh | ssh | < 4.9.1.5 | Yes |
| Application | ssh | ssh | < 4.11.1.7 | Yes |
| Application | ssh | ssh | < 4.13.2.4 | Yes |
| Application | ssh | ssh | < 4.15.3.1 | Yes |
| Application | ssh | ssh | < 5.1.1 | Yes |
| Operating System | thorntech | sftp_gateway_firmware | < 3.4.6 | Yes |
| Application | netgate | pfsense_plus | ≤ 23.09.1 | Yes |
| Application | netgate | pfsense_ce | ≤ 2.7.2 | Yes |
| Application | crushftp | crushftp | < 10.6.0 | Yes |
| Application | connectbot | sshlib | < 2.2.22 | Yes |
| Application | apache | sshd | ≤ 2.11.0 | Yes |
| Application | apache | sshj | ≤ 0.37.0 | Yes |
| Application | tinyssh | tinyssh | ≤ 20230101 | Yes |
| Application | trilead | ssh2 | 6401 | Yes |
| Application | 9bis | kitty | ≤ 0.76.1.13 | Yes |
| Application | gentoo | security | - | Yes |
| Operating System | debian | debian_linux | - | No |
| Operating System | fedoraproject | fedora | 38 | Yes |
| Operating System | fedoraproject | fedora | 39 | Yes |
| Operating System | debian | debian_linux | 10.0 | Yes |
| Operating System | apple | macos | < 14.4 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For openbsd's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.