--- title: "CVE-2023-48795: The SSH transport protocol with certain… | CubePath" description: "The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity…" language: en source: https://cubepath.com/security/cve/CVE-2023-48795 --- # CVE-2023-48795: The SSH transport protocol with certain… | CubePath ## Description 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 chacha20-poly1305@openssh.com and (if CBC is used) the -etm@openssh.com 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. Official description from the CVE record, published by mitre. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-48795) ## Key data ### CVSS 3.1 Medium 5.9 Score published by CISA-ADP in the CVE record. CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N | Metric | Value | What it means | | ---------------------- | --------- | ----------------------------------------------------------------------------------------- | | Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. | | Attack complexity | High | The attack depends on conditions outside the attacker's control, so it takes preparation. | | Privileges required | None | No account or privileges are needed. | | User interaction | None | No action from any user is needed. | | Scope | Unchanged | The impact stays within the vulnerable component. | | Confidentiality impact | None | No effect on the secrecy of data. | | Integrity impact | High | Serious or total effect on the trustworthiness of data. | | Availability impact | None | No effect on availability. | CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) . ### EPSS Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days. Score 0.93547 (93.5% probability) Percentile 99.8% Scores of Nov 10, 2026 Model v2026.06.15 ### CISA assessment as of Dec 22, 2023 Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA. Exploitation Public proof of concept recorded by CISA Automatable no Technical impact partial ### Weakness (CWE) CWE catalog version 5.0. CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license. - [CWE-354](https://cwe.mitre.org/data/definitions/354.html) Improper Validation of Integrity Check Value ## References Links listed in the CVE record. They lead to other sites, which CubePath does not control. - [chiark.greenend.org.uk/\~sgtatham/putty/changes.html](https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html) - [matt.ucc.asn.au/dropbear/CHANGES](https://matt.ucc.asn.au/dropbear/CHANGES) - [github.com/proftpd/proftpd/blob/master/RELEASE\_NOTES](https://github.com/proftpd/proftpd/blob/master/RELEASE%5FNOTES) - [netsarang.com/en/xshell-update-history](https://www.netsarang.com/en/xshell-update-history/) - [paramiko.org/changelog.html](https://www.paramiko.org/changelog.html) - [openssh.com/openbsd.html](https://www.openssh.com/openbsd.html) - [github.com/openssh/openssh-portable/commits/master](https://github.com/openssh/openssh-portable/commits/master) - [groups.google.com/g/golang-announce/c/-n5WqVC18LQ](https://groups.google.com/g/golang-announce/c/-n5WqVC18LQ) - [bitvise.com/ssh-server-version-history](https://www.bitvise.com/ssh-server-version-history) - [github.com/ronf/asyncssh/tags](https://github.com/ronf/asyncssh/tags) - [gitlab.com/libssh/libssh-mirror/-/tags](https://gitlab.com/libssh/libssh-mirror/-/tags) - [reddit.com/r/sysadmin/comments/18idv52/cve202348795\_why\_is\_…](https://www.reddit.com/r/sysadmin/comments/18idv52/cve202348795%5Fwhy%5Fis%5Fthis%5Fcve%5Fstill%5Fundisclosed/) - [github.com/erlang/otp/blob/d1b43dc0f1361d2ad67601169e90a7fc…](https://github.com/erlang/otp/blob/d1b43dc0f1361d2ad67601169e90a7fc50bb0369/lib/ssh/doc/src/notes.xml#L39-L42) - [openssh.com/txt/release-9.6](https://www.openssh.com/txt/release-9.6) - [jadaptive.com/important-java-ssh-security-update-new-ssh-vu…](https://jadaptive.com/important-java-ssh-security-update-new-ssh-vulnerability-discovered-cve-2023-48795/) - [terrapin-attack.com](https://www.terrapin-attack.com) - [github.com/mkj/dropbear/blob/17657c36cce6df7716d5ff151ec09a…](https://github.com/mkj/dropbear/blob/17657c36cce6df7716d5ff151ec09a665382d5dd/CHANGES#L25) - [github.com/ronf/asyncssh/blob/develop/docs/changes.rst](https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst) - [thorntech.com/cve-2023-48795-and-sftp-gateway](https://thorntech.com/cve-2023-48795-and-sftp-gateway/) - [github.com/warp-tech/russh/releases/tag/v0.40.2](https://github.com/warp-tech/russh/releases/tag/v0.40.2) - [github.com/TeraTermProject/teraterm/commit/7279fbd6ef4d0c8b…](https://github.com/TeraTermProject/teraterm/commit/7279fbd6ef4d0c8bdd6a90af4ada2899d786eec0) - [openwall.com/lists/oss-security/2023/12/18/2](https://www.openwall.com/lists/oss-security/2023/12/18/2) - [twitter.com/TrueSkrillor/status/1736774389725565005](https://twitter.com/TrueSkrillor/status/1736774389725565005) - [github.com/golang/crypto/commit/9d2ee975ef9fe627bf0a6f01c1f…](https://github.com/golang/crypto/commit/9d2ee975ef9fe627bf0a6f01c1f69e8ef1d4f05d) - [github.com/paramiko/paramiko/issues/2337](https://github.com/paramiko/paramiko/issues/2337) - [groups.google.com/g/golang-announce/c/qA3XtxvMUyg](https://groups.google.com/g/golang-announce/c/qA3XtxvMUyg) - [news.ycombinator.com/item?id=38684904](https://news.ycombinator.com/item?id=38684904) - [news.ycombinator.com/item?id=38685286](https://news.ycombinator.com/item?id=38685286) - [\[oss-security\] 20231218 CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)](http://www.openwall.com/lists/oss-security/2023/12/18/3) (openwall.com) mailing-list - [github.com/mwiede/jsch/issues/457](https://github.com/mwiede/jsch/issues/457) - [git.libssh.org/projects/libssh.git/commit/?h=stable-0.10&id…](https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.10&id=10e09e273f69e149389b3e0e5d44b8c221c2e7f6) - [github.com/erlang/otp/releases/tag/OTP-26.2.1](https://github.com/erlang/otp/releases/tag/OTP-26.2.1) - [github.com/advisories/GHSA-45x7-px36-x8w8](https://github.com/advisories/GHSA-45x7-px36-x8w8) - [security-tracker.debian.org/tracker/source-package/libssh2](https://security-tracker.debian.org/tracker/source-package/libssh2) - [security-tracker.debian.org/tracker/source-package/proftpd-…](https://security-tracker.debian.org/tracker/source-package/proftpd-dfsg) - [security-tracker.debian.org/tracker/CVE-2023-48795](https://security-tracker.debian.org/tracker/CVE-2023-48795) - [bugzilla.suse.com/show\_bug.cgi?id=1217950](https://bugzilla.suse.com/show%5Fbug.cgi?id=1217950) - [bugzilla.redhat.com/show\_bug.cgi?id=2254210](https://bugzilla.redhat.com/show%5Fbug.cgi?id=2254210) - [bugs.gentoo.org/920280](https://bugs.gentoo.org/920280) - [ubuntu.com/security/CVE-2023-48795](https://ubuntu.com/security/CVE-2023-48795) - [suse.com/c/suse-addresses-the-ssh-v2-protocol-terrapin-atta…](https://www.suse.com/c/suse-addresses-the-ssh-v2-protocol-terrapin-attack-aka-cve-2023-48795/) - [access.redhat.com/security/cve/cve-2023-48795](https://access.redhat.com/security/cve/cve-2023-48795) - [github.com/mwiede/jsch/pull/461](https://github.com/mwiede/jsch/pull/461) - [github.com/drakkan/sftpgo/releases/tag/v2.5.6](https://github.com/drakkan/sftpgo/releases/tag/v2.5.6) - [github.com/libssh2/libssh2/pull/1291](https://github.com/libssh2/libssh2/pull/1291) - [forum.netgate.com/topic/184941/terrapin-ssh-attack](https://forum.netgate.com/topic/184941/terrapin-ssh-attack) - [github.com/jtesta/ssh-audit/commit/8e972c5e94b460379fe0c7d2…](https://github.com/jtesta/ssh-audit/commit/8e972c5e94b460379fe0c7d20209c16df81538a5) - [github.com/rapier1/hpn-ssh/releases](https://github.com/rapier1/hpn-ssh/releases) - [github.com/proftpd/proftpd/issues/456](https://github.com/proftpd/proftpd/issues/456) - [github.com/TeraTermProject/teraterm/releases/tag/v5.1](https://github.com/TeraTermProject/teraterm/releases/tag/v5.1) - [github.com/mwiede/jsch/compare/jsch-0.2.14...jsch-0.2.15](https://github.com/mwiede/jsch/compare/jsch-0.2.14...jsch-0.2.15) - [oryx-embedded.com/download](https://oryx-embedded.com/download/#changelog) - [crushftp.com/crush10wiki/Wiki.jsp?page=Update](https://www.crushftp.com/crush10wiki/Wiki.jsp?page=Update) - [github.com/connectbot/sshlib/compare/2.2.21...2.2.22](https://github.com/connectbot/sshlib/compare/2.2.21...2.2.22) - [github.com/connectbot/sshlib/commit/5c8b534f6e97db7ac0e0e57…](https://github.com/connectbot/sshlib/commit/5c8b534f6e97db7ac0e0e579331213aa25c173ab) - [github.com/mscdex/ssh2/commit/97b223f8891b96d6fc054df5ab1d5…](https://github.com/mscdex/ssh2/commit/97b223f8891b96d6fc054df5ab1d5a1a545da2a3) - [nest.pijul.com/pijul/thrussh/changes/D6H7OWTTMHHX6BTB3B6MNB…](https://nest.pijul.com/pijul/thrussh/changes/D6H7OWTTMHHX6BTB3B6MNBOBX2L66CBL4LGSEUSAI2MCRCJDQFRQC) - [crates.io/crates/thrussh/versions](https://crates.io/crates/thrussh/versions) - [github.com/NixOS/nixpkgs/pull/275249](https://github.com/NixOS/nixpkgs/pull/275249) - [\[oss-security\] 20231219 Re: CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)](http://www.openwall.com/lists/oss-security/2023/12/19/5) (openwall.com) mailing-list - [freebsd.org/security/advisories/FreeBSD-SA-23:19.openssh.asc](https://www.freebsd.org/security/advisories/FreeBSD-SA-23:19.openssh.asc) - [arstechnica.com/security/2023/12/hackers-can-break-ssh-chan…](https://arstechnica.com/security/2023/12/hackers-can-break-ssh-channel-integrity-using-novel-data-corruption-attack/) - [\[oss-security\] 20231220 Re: CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)](http://www.openwall.com/lists/oss-security/2023/12/20/3) (openwall.com) mailing-list - [packetstormsecurity.com/files/176280/Terrapin-SSH-Connectio…](http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html) - [github.com/proftpd/proftpd/blob/d21e7a2e47e9b38f709bec58e3f…](https://github.com/proftpd/proftpd/blob/d21e7a2e47e9b38f709bec58e3fa711f759ad0e1/RELEASE%5FNOTES) - [github.com/proftpd/proftpd/blob/0a7ea9b0ba9fcdf368374a22637…](https://github.com/proftpd/proftpd/blob/0a7ea9b0ba9fcdf368374a226370d08f10397d99/RELEASE%5FNOTES) - [github.com/apache/mina-sshd/issues/445](https://github.com/apache/mina-sshd/issues/445) - [github.com/hierynomus/sshj/issues/916](https://github.com/hierynomus/sshj/issues/916) - [github.com/janmojzis/tinyssh/issues/81](https://github.com/janmojzis/tinyssh/issues/81) - [openwall.com/lists/oss-security/2023/12/20/3](https://www.openwall.com/lists/oss-security/2023/12/20/3) - [security-tracker.debian.org/tracker/source-package/trilead-…](https://security-tracker.debian.org/tracker/source-package/trilead-ssh2) - [github.com/net-ssh/net-ssh/blob/2e65064a52d73396bfc3806c919…](https://github.com/net-ssh/net-ssh/blob/2e65064a52d73396bfc3806c9196fc8108f33cd8/CHANGES.txt#L14-L16) - [FEDORA-2023-0733306be9](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MKQRBF3DWMWPH36LBCOBUTSIZRTPEZXB/) (lists.fedoraproject.org) vendor-advisory - [DSA-5586](https://www.debian.org/security/2023/dsa-5586) (debian.org) vendor-advisory - [lancom-systems.de/service-support/allgemeine-sicherheitshin…](https://www.lancom-systems.de/service-support/allgemeine-sicherheitshinweise#c243508) - [theregister.com/2023/12/20/terrapin\_attack\_ssh](https://www.theregister.com/2023/12/20/terrapin%5Fattack%5Fssh) - [filezilla-project.org/versions.php](https://filezilla-project.org/versions.php) - [nova.app/releases](https://nova.app/releases/#v11.8) - [roumenpetrov.info/secsh](https://roumenpetrov.info/secsh/#news20231220) - [vandyke.com/products/securecrt/history.txt](https://www.vandyke.com/products/securecrt/history.txt) - [help.panic.com/releasenotes/transmit5](https://help.panic.com/releasenotes/transmit5/) - [github.com/PowerShell/Win32-OpenSSH/releases/tag/v9.5.0.0p1…](https://github.com/PowerShell/Win32-OpenSSH/releases/tag/v9.5.0.0p1-Beta) - [github.com/PowerShell/Win32-OpenSSH/issues/2189](https://github.com/PowerShell/Win32-OpenSSH/issues/2189) - [winscp.net/eng/docs/history](https://winscp.net/eng/docs/history#6.2.2) - [bitvise.com/ssh-client-version-history](https://www.bitvise.com/ssh-client-version-history#933) - [github.com/cyd01/KiTTY/issues/520](https://github.com/cyd01/KiTTY/issues/520) - [DSA-5588](https://www.debian.org/security/2023/dsa-5588) (debian.org) vendor-advisory - [github.com/ssh-mitm/ssh-mitm/issues/165](https://github.com/ssh-mitm/ssh-mitm/issues/165) - [news.ycombinator.com/item?id=38732005](https://news.ycombinator.com/item?id=38732005) - [\[debian-lts-announce\] 20231226 \[SECURITY\] \[DLA 3694-1\] openssh security update](https://lists.debian.org/debian-lts-announce/2023/12/msg00017.html) (lists.debian.org) mailing-list - [GLSA-202312-16](https://security.gentoo.org/glsa/202312-16) (security.gentoo.org) vendor-advisory - [GLSA-202312-17](https://security.gentoo.org/glsa/202312-17) (security.gentoo.org) vendor-advisory - [FEDORA-2023-20feb865d8](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YQLUQWLIHDB5QCXQEX7HXHAWMOKPP5O/) (lists.fedoraproject.org) vendor-advisory - [FEDORA-2023-cb8c606fbb](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/F7EYCFQCTSGJXWO3ZZ44MGKFC5HA7G3Y/) (lists.fedoraproject.org) vendor-advisory - [FEDORA-2023-e77300e4b5](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/APYIXIQOVDCRWLHTGB4VYMAUIAQLKYJ3/) (lists.fedoraproject.org) vendor-advisory - [FEDORA-2023-b87ec6cf47](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QI3EHAHABFQK7OABNCSF5GMYP6TONTI7/) (lists.fedoraproject.org) vendor-advisory - [FEDORA-2023-153404713b](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KMZCVGUGJZZVDPCVDA7TEB22VUCNEXDD/) (lists.fedoraproject.org) vendor-advisory - [security.netapp.com/advisory/ntap-20240105-0004](https://security.netapp.com/advisory/ntap-20240105-0004/) - [FEDORA-2024-3bb23c77f3](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3CAYYW35MUTNO65RVAELICTNZZFMT2XS/) (lists.fedoraproject.org) vendor-advisory - [FEDORA-2023-55800423a8](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LZQVUHWVWRH73YBXUQJOD6CKHDQBU3DM/) (lists.fedoraproject.org) vendor-advisory and 34 more in the [record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-48795) ## Timeline 1. ID reserved Nov 20, 2023 2. Record published Dec 18, 2023 3. Record last updated Oct 15, 2026 ## Look up another CVE ## About CubePath CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection. [Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection) Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 20:02 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)