CVE-2023-48795: OpenSSH Terrapin attack (CVE-2023-48795)

Published Dec 12, 2023
·
Updated

Summary

Terrapin is a prefix truncation attack targeting the SSH protocol. More precisely, Terrapin breaks the integrity of SSH's secure channel. By carefully adjusting the sequence numbers during the handshake, an attacker can remove an arbitrary amount of messages sent by the client or server at the beginning of the secure channel without the client or server noticing it.

Mitigations

To mitigate this protocol vulnerability, OpenSSH suggested a so-called "strict kex" which alters the SSH handshake to ensure a Man-in-the-Middle attacker cannot introduce unauthenticated messages as well as convey sequence number manipulation across handshakes.

Warning: To take effect, both the client and server must support this countermeasure.

As a stop-gap measure, peers may also (temporarily) disable the affected algorithms and use unaffected alternatives like AES-GCM instead until patches are available.

Details

The SSH specifications of ChaCha20-Poly1305 (chacha20-poly1305@openssh.com) and Encrypt-then-MAC (-etm@openssh.com MACs) are vulnerable against an arbitrary prefix truncation attack (a.k.a. Terrapin attack). This allows for an extension negotiation downgrade by stripping the SSHMSGEXTINFO sent after the first message after SSHMSGNEWKEYS, downgrading security, and disabling attack countermeasures in some versions of OpenSSH. When targeting Encrypt-then-MAC, this attack requires the use of a CBC cipher to be practically exploitable due to the internal workings of the cipher mode. Additionally, this novel attack technique can be used to exploit previously unexploitable implementation flaws in a Man-in-the-Middle scenario.

The attack works by an attacker injecting an arbitrary number of SSHMSGIGNORE messages during the initial key exchange and consequently removing the same number of messages just after the initial key exchange has concluded. This is possible due to missing authentication of the excess SSHMSGIGNORE messages and the fact that the implicit sequence numbers used within the SSH protocol are only checked after the initial key exchange.

In the case of ChaCha20-Poly1305, the attack is guaranteed to work on every connection as this cipher does not maintain an internal state other than the message's sequence number. In the case of Encrypt-Then-MAC, practical exploitation requires the use of a CBC cipher; while theoretical integrity is broken for all ciphers when using this mode, message processing will fail at the application layer for CTR and stream ciphers.

For more details see https://terrapin-attack.com.

Impact

This attack targets the specification of ChaCha20-Poly1305 (chacha20-poly1305@openssh.com) and Encrypt-then-MAC (-etm@openssh.com), which are widely adopted by well-known SSH implementations and can be considered de-facto standard. These algorithms can be practically exploited; however, in the case of Encrypt-Then-MAC, we additionally require the use of a CBC cipher. As a consequence, this attack works against all well-behaving SSH implementations supporting either of those algorithms and can be used to downgrade (but not fully strip) connection security in case SSH extension negotiation (RFC8308) is supported. The attack may also enable attackers to exploit certain implementation flaws in a man-in-the-middle (MitM) scenario.

Other sources

Accessibility. A privacy issue was addressed with improved private data redaction for log entries.

— Apple

Admin Framework. A logic issue was addressed with improved checks.

— Apple

Airport. This issue was addressed with improved redaction of sensitive information.

— Apple

AppKit. A logic issue was addressed with improved restrictions.

— Apple

AppleMobileFileIntegrity. A downgrade issue affecting Intel-based Mac computers was addressed with additional code-signing restrictions.

— Apple

Credit

CVE-2023-48795, CVE-2023-51384, CVE-2023-51385, CVE-2024-23225, koocola, an anonymous researcher, ali yabuz, Kirin@@Pwnrin, Meysam Firouzi@@R00tkitsmm(Trend Micro Zero Day Initiative), @@08Tc3wBB(Jamf), CVE-2024-23283, Mickey Jin@@patch1t, Pedro Tôrres@@t0rr3sp3dr0, Bohdan Stasiuk@@Bohdan_Stasiuk, Harsh Tyagi, Wojciech Regula(SecuRing), CVE-2024-23296, Lyra Rebane (rebane2001), Matej Rabzelj, CVE-2024-23238, Yiğit Can YILMAZ@@yilmazcanyigit, luckyu@@uuulucky, K宝(Fudan University), LFY@@secsys(Fudan University), Lewis Hardy, Bistrit Dahal, CVE-2024-23241, CVE-2024-23242, Joshua Jewett@@JoshJewett33, Matthew Loewen, Deutsche Telekom Security GmbH sponsored by Bundesamt für Sicherheit in der Informationstechnik, anbu1024(SecANT), Pwn2car, James Lee@@Windowsrcer, Johan Carlsson (joaxcar), Georg Felber, Marco Squarcina, Junsung Lee(Trend Micro Zero Day Initiative), Zhenjiang Zhao(pangu team), Qianxin(CrowdStrike Counter Adversary Operations), (CrowdStrike Counter Adversary Operations), Amir Bazine(CrowdStrike Counter Adversary Operations), Karsten König(CrowdStrike Counter Adversary Operations), Dohyun Lee@@l33d0hyun, Lyutoon, Mr.R, Murray Mike, CVE-2024-23235, Xinru Chi(Pangu Lab), m4yfly with TianGong Team(Legendsec at Qi'anxin Group), Guilherme Rambo(Best Buddy Apps), Csaba Fitzl@@theevilbit(OffSec), CVE-2024-23205, CVE-2022-48554, Marc Newlin(SkySafe), Brian McNulty, Stephan Casas, CVE-2024-23291

Affected Software

162 affected componentsFixes available
Apple macOS Sonoma<14.4
14.4
Fortinet FortiAnalyzer=.
Fortinet FortiAnalyzer=.
Fortinet FortiEDR Manager>=6.2.0<=6.2.4
Fortinet FortiEDR Manager>=6.0
Fortinet FortiEDR Manager>=5.2
Fortinet FortiEDR Manager>=5.1
Fortinet FortiEDR Manager>=5.0
Fortinet FortiMail>=7.4.0<=7.4.1
Fortinet FortiMail>=7.2.0<=7.2.5
Fortinet FortiMail>=7.0.0<=7.0.7
Fortinet FortiMail>=6.4
Fortinet FortiMail>=6.2
Fortinet FortiManager=.
Fortinet FortiManager=.
Fortinet FortiNAC-F>=7.2.0<=7.2.5
Fortinet FortiNDR>=7.4.0<=7.4.2
Fortinet FortiNDR>=7.2.0<=7.2.1
Fortinet FortiNDR>=7.1
Fortinet FortiNDR>=7.0.0<=7.0.5
Fortinet FortiRecorder>=7.0.0<=7.0.3
Fortinet FortiRecorder>=6.4
Fortinet FortiRecorder>=6.0
Fortinet FortiSIEM>=7.1.0<=7.1.3
Fortinet FortiSIEM>=7.0
Fortinet FortiSIEM>=6.7
Fortinet FortiSIEM>=6.6
Fortinet FortiSIEM>=6.5
Fortinet FortiSIEM>=6.4
Fortinet FortiSIEM>=6.3
Fortinet FortiSIEM>=6.2
Fortinet FortiSIEM>=6.1
Fortinet FortiSIEM>=5.4
Fortinet FortiSIEM>=5.3
Fortinet FortiSOAR>=7.4.0<=7.4.2
Fortinet FortiSOAR>=7.3
Fortinet FortiSOAR>=7.2
Fortinet FortiVoice>=7.0.0<=7.0.1
Fortinet FortiVoice>=6.4.0<=6.4.8
Fortinet FortiVoice>=6.0.0<=6.0.12
Fortinet FortiWeb>=7.4.0<=7.4.2
Fortinet FortiWeb>=7.2.0<=7.2.7
Fortinet FortiWeb>=7.0.0<=7.0.10
Fortinet FortiWeb>=6.4
Fortinet FortiWeb>=6.3
Fortinet FortiWeb>=6.2
go/golang.org/x/crypto<0.0.0-20231218163308-9d2ee975ef9f
0.0.0-20231218163308-9d2ee975ef9f
go/golang.org/x/crypto>=0.1.0<0.17.0
0.17.0
pip/paramiko>=2.5.0<3.4.0
3.4.0
rust/russh<0.40.2
0.40.2
IBM QRadar Network Packet Capture<=7.5.0 - 7.5.0 Update Package 7
Palo Alto Networks PAN-OS=9.0.0, =9.1.0, =10.1.0, <10.2.14, =10.2.0, =11.0.0, <11.1.8, =11.1.0, <11.2.8, =11.2.0
10.2.1411.1.811.2.8
Palo Alto Networks Prisma SD-WAN ION<5.6.19, =5.6, <6.1.8, =6.1, =6.2, <6.3.2, =6.3
5.6.196.1.86.3.2
OpenBSD OpenSSH<9.6
Putty PuTTY<0.80
Filezilla-project Filezilla Client<3.66.4
All of the following
Apple macOS
Panic Transmit 5<5.10.4
All of the following
Apple macOS
Panic Nova<11.8
Roumenpetrov Pkixssh<14.4
WinSCP WinSCP<6.2.2
Bitvise SSH Client<9.33
Bitvise SSH Server<9.32
Lancom-systems Lcos<=3.66.4
Lancom-systems Lcos Fx
Lancom-systems Lcos Lx
Lancom-systems Lcos Sx=4.20
Lancom-systems Lcos Sx=5.20
Lancom-systems Lanconfig
VanDyke Securecrt<9.4.3
libssh libssh<0.10.6
net-ssh Net-ssh Ruby=7.2.0
Ssh2 Project Ssh2 Node.js<=1.11.0
ProFTPD ProFTPD<=1.3.8b
FreeBSD FreeBSD<=12.4
Crates Thrussh<0.35.1
Tera Term Project Tera Term<=5.1
Oryx-embedded Cyclone Ssh<2.3.4
CrushFTP CrushFTP<=10.6.0
NetSarang XShell 7<build__0144
Paramiko Paramiko<3.4.0
redhat OpenShift Container Platform=4.0
redhat Openstack Platform=16.1
redhat Openstack Platform=16.2
redhat Openstack Platform=17.1
redhat Ceph Storage=6.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux=9.0
redhat Openshift Serverless
redhat Openshift Gitops
redhat Openshift Pipelines
redhat Openshift Developer Tools And Services
redhat Openshift Data Foundation=4.0
redhat Openshift Api For Data Protection
redhat Openshift Virtualization=4
redhat Storage=3.0
redhat Discovery
redhat Openshift Dev Spaces
redhat Cert-manager Operator For Red Hat Openshift
redhat keycloak
redhat JBoss Enterprise Application Platform=7.0
redhat Single Sign-on=7.0
redhat Advanced Cluster Security=3.0
redhat Advanced Cluster Security=4.0
Golang crypto<0.17.0
Russh Project Russh Rust<0.40.2
Sftpgo Project Sftpgo<2.5.6
Erlang Erlang\/otp<22.3.4.27
Erlang Erlang\/otp>=23.0<23.3.4.20
Erlang Erlang\/otp>=24.0<24.3.4.15
Erlang Erlang\/otp>=25.0<25.3.2.8
Erlang Erlang\/otp>=26.0<26.2.1
Matez Jsch<0.2.15
libssh2 libssh2<1.11.1
Asyncssh Project Asyncssh<2.14.2
Dropbear Ssh Project Dropbear Ssh<2022.83
Jadaptive Maverick Synergy Java Ssh Api<3.1.0-snapshot
SSH ssh<4.9.1.5
SSH ssh>=4.10<4.11.1.7
SSH ssh>=4.12<4.13.2.4
SSH ssh>=4.14<4.15.3.1
SSH ssh>=5.0<5.1.1
Thorntech Sftp Gateway Firmware<3.4.6
Netgate pfSense Plus<=23.09.1
Netgate pfSense CE<=2.7.2
CrushFTP CrushFTP<10.6.0
ConnectBot Sshlib<2.2.22
Apache sshd<=2.11.0
Apache sshj<=0.37.0
TinySSH TinySSH<=20230101
trilead ssh2=6401
9bis Kitty<=0.76.1.13
All of the following
Gentoo Security
Debian Debian Linux
Fedoraproject Fedora=38
Fedoraproject Fedora=39
Debian Debian Linux=10.0
Apple macOS>=14.0<14.4
redhat/PuTTY<0.80
0.80
redhat/AsyncSSH<2.14.1
2.14.1
redhat/libssh<0.9.8
0.9.8
redhat/libssh<0.10.6
0.10.6
redhat/golang.org/x/crypto/ssh<0.17.0
0.17.0
debian/dropbear
2020.81-3+deb11u22020.81-3+deb11u32022.83-1+deb12u32025.89-1~deb13u12026.93-12026.94-1
debian/erlang<=1:23.2.6+dfsg-1+deb11u1
1:23.2.6+dfsg-1+deb11u41:25.2.3+dfsg-1+deb12u41:25.2.3+dfsg-1+deb12u11:27.3.4.1+dfsg-1+deb13u21:29.0.3+dfsg-1
debian/filezilla
3.52.2-3+deb11u13.63.0-1+deb12u33.68.1-13.70.6-2
debian/golang-go.crypto<=1:0.0~git20201221.eec23a3-1, <=1:0.4.0-1
1:0.25.0-11:0.53.0-1
debian/jsch
0.1.55-10.2.19-1
debian/libssh
0.9.8-0+deb11u10.9.8-0+deb11u20.10.6-0+deb12u20.10.6-0+deb12u10.11.2-1+deb13u10.12.0-3
debian/libssh2
1.9.0-2+deb11u11.10.0-31.11.1-1+deb13u11.11.1-4
debian/openssh
1:8.4p1-5+deb11u31:8.4p1-5+deb11u71:9.2p1-2+deb12u101:9.2p1-2+deb12u91:10.0p1-7+deb13u41:10.0p1-7+deb13u21:10.3p1-51:10.4p1-2
debian/paramiko<=2.7.2-1, <=2.7.2-1+deb11u1, <=2.12.0-2
3.5.1-34.0.0-4
debian/php-phpseclib
2.0.30-2+deb11u22.0.30-2+deb11u32.0.42-1+deb12u52.0.42-1+deb12u32.0.48-3+deb13u32.0.48-3+deb13u12.0.55-1
debian/php-phpseclib3
3.0.19-1+deb12u63.0.19-1+deb12u43.0.43-2+deb13u33.0.43-2+deb13u13.0.55-1
debian/phpseclib
1.0.19-3+deb11u21.0.19-3+deb11u31.0.20-1+deb12u51.0.20-1+deb12u31.0.23-6+deb13u31.0.23-6+deb13u11.0.30-1
debian/proftpd-dfsg<=1.3.7a+dfsg-12+deb11u2
1.3.7a+dfsg-12+deb11u51.3.8+dfsg-4+deb12u51.3.8+dfsg-4+deb12u41.3.8.c+dfsg-4+deb13u21.3.9c~dfsg-1
debian/proftpd-mod-proxy<=0.7-1
0.9.2-1+deb12u10.9.5-10.9.7-1
debian/putty
0.74-1+deb11u20.74-1+deb11u10.78-2+deb12u20.78-2+deb12u10.83-30.84-1
debian/python-asyncssh<=2.5.0-0.1
2.5.0-0.1+deb11u12.10.1-2+deb12u22.10.1-2+deb12u12.20.0-12.23.0-1
debian/tinyssh<=20190101-1+deb11u1, <=20230101-1
20250501-120260601-1
debian/trilead-ssh2<=6401+svn158-1.1, <=6401+svn158-2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Apple macOS to a version that resolves this vulnerability.

    Fixed in 14.4
  2. Upgrade

    Upgrade go/golang.org/x/crypto to a version that resolves this vulnerability.

    Fixed in 0.0.0-20231218163308-9d2ee975ef9f
  3. Upgrade

    Upgrade go/golang.org/x/crypto to a version that resolves this vulnerability.

    Fixed in 0.17.0
  4. Upgrade

    Upgrade pip/paramiko to a version that resolves this vulnerability.

    Fixed in 3.4.0
  5. Upgrade

    Upgrade rust/russh to a version that resolves this vulnerability.

    Fixed in 0.40.2
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.2.14Fixed in 11.1.8Fixed in 11.2.8
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 5.6.19Fixed in 6.1.8Fixed in 6.3.2
  8. Upgrade

    Upgrade redhat/PuTTY to a version that resolves this vulnerability.

    Fixed in 0.80
  9. Upgrade

    Upgrade redhat/AsyncSSH to a version that resolves this vulnerability.

    Fixed in 2.14.1
  10. Upgrade

    Upgrade redhat/libssh to a version that resolves this vulnerability.

    Fixed in 0.9.8
  11. Upgrade

    Upgrade redhat/libssh to a version that resolves this vulnerability.

    Fixed in 0.10.6
  12. Upgrade

    Upgrade redhat/golang.org/x/crypto/ssh to a version that resolves this vulnerability.

    Fixed in 0.17.0
  13. Upgrade

    Upgrade debian/dropbear to a version that resolves this vulnerability.

    Fixed in 2020.81-3+deb11u2Fixed in 2020.81-3+deb11u3Fixed in 2022.83-1+deb12u3Fixed in 2025.89-1~deb13u1Fixed in 2026.93-1Fixed in 2026.94-1
  14. Upgrade

    Upgrade debian/erlang to a version that resolves this vulnerability.

    Fixed in 1:23.2.6+dfsg-1+deb11u4Fixed in 1:25.2.3+dfsg-1+deb12u4Fixed in 1:25.2.3+dfsg-1+deb12u1Fixed in 1:27.3.4.1+dfsg-1+deb13u2Fixed in 1:29.0.3+dfsg-1
  15. Upgrade

    Upgrade debian/filezilla to a version that resolves this vulnerability.

    Fixed in 3.52.2-3+deb11u1Fixed in 3.63.0-1+deb12u3Fixed in 3.68.1-1Fixed in 3.70.6-2
  16. Upgrade

    Upgrade debian/golang-go.crypto to a version that resolves this vulnerability.

    Fixed in 1:0.25.0-1Fixed in 1:0.53.0-1
  17. Upgrade

    Upgrade debian/jsch to a version that resolves this vulnerability.

    Fixed in 0.1.55-1Fixed in 0.2.19-1
  18. Upgrade

    Upgrade debian/libssh to a version that resolves this vulnerability.

    Fixed in 0.9.8-0+deb11u1Fixed in 0.9.8-0+deb11u2Fixed in 0.10.6-0+deb12u2Fixed in 0.10.6-0+deb12u1Fixed in 0.11.2-1+deb13u1Fixed in 0.12.0-3
  19. Upgrade

    Upgrade debian/libssh2 to a version that resolves this vulnerability.

    Fixed in 1.9.0-2+deb11u1Fixed in 1.10.0-3Fixed in 1.11.1-1+deb13u1Fixed in 1.11.1-4
  20. Upgrade

    Upgrade debian/openssh to a version that resolves this vulnerability.

    Fixed in 1:8.4p1-5+deb11u3Fixed in 1:8.4p1-5+deb11u7Fixed in 1:9.2p1-2+deb12u10Fixed in 1:9.2p1-2+deb12u9Fixed in 1:10.0p1-7+deb13u4Fixed in 1:10.0p1-7+deb13u2Fixed in 1:10.3p1-5Fixed in 1:10.4p1-2
  21. Upgrade

    Upgrade debian/paramiko to a version that resolves this vulnerability.

    Fixed in 3.5.1-3Fixed in 4.0.0-4
  22. Upgrade

    Upgrade debian/php-phpseclib to a version that resolves this vulnerability.

    Fixed in 2.0.30-2+deb11u2Fixed in 2.0.30-2+deb11u3Fixed in 2.0.42-1+deb12u5Fixed in 2.0.42-1+deb12u3Fixed in 2.0.48-3+deb13u3Fixed in 2.0.48-3+deb13u1Fixed in 2.0.55-1
  23. Upgrade

    Upgrade debian/php-phpseclib3 to a version that resolves this vulnerability.

    Fixed in 3.0.19-1+deb12u6Fixed in 3.0.19-1+deb12u4Fixed in 3.0.43-2+deb13u3Fixed in 3.0.43-2+deb13u1Fixed in 3.0.55-1
  24. Upgrade

    Upgrade debian/phpseclib to a version that resolves this vulnerability.

    Fixed in 1.0.19-3+deb11u2Fixed in 1.0.19-3+deb11u3Fixed in 1.0.20-1+deb12u5Fixed in 1.0.20-1+deb12u3Fixed in 1.0.23-6+deb13u3Fixed in 1.0.23-6+deb13u1Fixed in 1.0.30-1
  25. Upgrade

    Upgrade debian/proftpd-dfsg to a version that resolves this vulnerability.

    Fixed in 1.3.7a+dfsg-12+deb11u5Fixed in 1.3.8+dfsg-4+deb12u5Fixed in 1.3.8+dfsg-4+deb12u4Fixed in 1.3.8.c+dfsg-4+deb13u2Fixed in 1.3.9c~dfsg-1
  26. Upgrade

    Upgrade debian/proftpd-mod-proxy to a version that resolves this vulnerability.

    Fixed in 0.9.2-1+deb12u1Fixed in 0.9.5-1Fixed in 0.9.7-1
  27. Upgrade

    Upgrade debian/putty to a version that resolves this vulnerability.

    Fixed in 0.74-1+deb11u2Fixed in 0.74-1+deb11u1Fixed in 0.78-2+deb12u2Fixed in 0.78-2+deb12u1Fixed in 0.83-3Fixed in 0.84-1
  28. Upgrade

    Upgrade debian/python-asyncssh to a version that resolves this vulnerability.

    Fixed in 2.5.0-0.1+deb11u1Fixed in 2.10.1-2+deb12u2Fixed in 2.10.1-2+deb12u1Fixed in 2.20.0-1Fixed in 2.23.0-1
  29. Upgrade

    Upgrade debian/tinyssh to a version that resolves this vulnerability.

    Fixed in 20250501-1Fixed in 20260601-1
  30. Upgrade

    Upgrade PAN-OS SSH client to a version that resolves this vulnerability.

    Fixed in 10.2.11
  31. Upgrade

    Upgrade PAN-OS SSH client to a version that resolves this vulnerability.

    Fixed in 11.0.6
  32. Upgrade

    Upgrade PAN-OS SSH client to a version that resolves this vulnerability.

    Fixed in 11.1.3
  33. Upgrade

    Upgrade PAN-OS SSH server to a version that resolves this vulnerability.

    Fixed in 10.2.14
  34. Upgrade

    Upgrade PAN-OS SSH server to a version that resolves this vulnerability.

    Fixed in 11.1.8
  35. Upgrade

    Upgrade PAN-OS SSH server to a version that resolves this vulnerability.

    Fixed in 11.2.8
  36. Upgrade

    Upgrade Prisma SD-WAN ION to a version that resolves this vulnerability.

    Fixed in 5.6.19
  37. Upgrade

    Upgrade Prisma SD-WAN ION to a version that resolves this vulnerability.

    Fixed in 6.1.8
  38. Upgrade

    Upgrade Prisma SD-WAN ION to a version that resolves this vulnerability.

    Fixed in 6.3.2
  39. Configuration

    As a stop-gap workaround until patches are available, configure the in-use SSH profile so it contains at least one cipher and at least one MAC algorithm; this removes support for CHACHA20-POLY1305 and all Encrypt-then-MAC algorithms in PAN-OS software.

    PAN-OS SSH profile (management interface) in-use SSH profile ciphers/MACs = Configure at least one cipher and at least one MAC algorithm (removes CHACHA20-POLY1305 and all *-etm@openssh.com Encrypt-then-MAC algorithms).
  40. Compensating control

    If using the PAN-OS SSH client to connect to an external SSH server, ensure that the external SSH server does not support the CHACHA20-POLY1305 algorithm or any Encrypt-then-MAC algorithms.

  41. Compensating control

    Use a PAN-OS configuration that removes support for the impacted algorithms: configure the system to exclusively use strong cipher algorithms or operate in FIPS-CC mode (this removes support for the impacted algorithms and prevents exploitation of this issue).

Event History

Dec 12, 2023
Data Sourced
via Red Hat·04:59 PM
DescriptionSeverityAffected Software
Dec 18, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Advisory Published
via GitHub·07:22 PM
Data Sourced
via GitHub·07:22 PM
DescriptionSeverityWeaknessAffected Software
Dec 19, 2023
News Published
05:03 PM
Dec 20, 2023
News Published
via The Register·08:34 AM
Jan 9, 2024
Advisory Published
via FortiGuard·12:00 AM
Advisory Published
via Palo Alto Networks·01:30 AM
Data Sourced
via Palo Alto Networks·01:30 AM
RemedyDescriptionSeverityWeaknessAffected Software
Jan 19, 2024
News Published
via The Register·09:51 PM
Jul 23, 2024
Data Sourced
via IBM·12:00 AM
DescriptionSeverityAffected Software
May 13, 2025
Advisory Published
via FortiGuard·02:55 PM
Jul 17, 2025
Data Sourced
via Ubuntu·02:30 PM
RemedyDescriptionSeverityAffected Software
Aug 30, 2025
Data Sourced
via Launchpad·02:37 PM
Description
Mar 10, 2026
Advisory Published
via Palo Alto Networks·01:00 AM
Jul 26, 2026
Data Sourced
via Debian·12:50 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2023-48795?

CVE-2023-48795 has been classified as a high severity vulnerability affecting the integrity of the SSH protocol.

2

How do I fix CVE-2023-48795?

To fix CVE-2023-48795, upgrade to the recommended versions of affected software such as Paramiko 3.4.0 or higher, and ensure all SSH implementations are updated accordingly.

3

What types of software are affected by CVE-2023-48795?

CVE-2023-48795 impacts various SSH implementations including Paramiko, OpenSSH, PuTTY, and several other cryptographic libraries.

4

Can CVE-2023-48795 be exploited remotely?

Yes, CVE-2023-48795 can be exploited remotely by attackers during the SSH handshake process.

5

What is the nature of the attack described in CVE-2023-48795?

CVE-2023-48795 refers to a prefix truncation attack, which compromises the integrity of the SSH secure channel.

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132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
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