CVE-2024-39894
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password...
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.5
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
CVE-2024-39894- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-367
- Updated
- 2026-11-02
EUVDEUVD-2024-38350
7.5
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
EUVD-2024-38350- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-g5qj-pfmg-p3jp
7.5
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password...
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
GHSA-g5qj-pfmg-p3jp- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-367
- Updated
- 2026-11-02
NVD
7.5
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
CVE-2024-39894- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-367
- Updated
- 2026-11-02
OSVBELL-CVE-2024-39894
7.5
- Record
BELL-CVE-2024-39894- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2024-39894
7.5
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
DEBIAN-CVE-2024-39894- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Show 7 moreShow less
OSVUBUNTU-CVE-2024-39894
7.5
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
UBUNTU-CVE-2024-39894- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVAZL-43140 No score
CVE-2024-39894 affecting package openssh for versions less than 9.8p1-1
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
AZL-43140- Updated
- 2026-11-02
OSV No score
OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.
- Record
CVE-2024-39894- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:14113-1 No score
openssh-9.6p1-11.1 on GA media
These are all security issues fixed in the openssh-9.6p1-11.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:14113-1- Updated
- 2026-11-02
OSVSUSE-SU-2024:2393-1 No score
Security update for openssh
This update for openssh fixes the following issues:
Security fixes:
- CVE-2024-39894: Fixed timing attacks against echo-off password entry (bsc#1227318).
Other fixes:
- Add obsoletes for openssh-server-config-rootlogin (bsc#1227350).
- Add #include <stdlib.h> in some files added by the ldap patch to fix build with gcc14 (bsc#1225904).
- Remove the recommendation for openssh-server-config-rootlogin from openssh-server (bsc#1224392).
- Record
SUSE-SU-2024:2393-1- Updated
- 2026-11-02
OSVSUSE-SU-2025:20009-1 No score
Security update for openssh
This update for openssh fixes the following issues:
- CVE-2024-39894: Fixed timing attacks against echo-off password entry (bsc#1227318)
- CVE-2024-6387: Fixed race condition in a signal handler (bsc#1226642).
- Record
SUSE-SU-2025:20009-1- Updated
- 2026-11-02
OSVUSN-6887-1 No score
openssh vulnerability
Philippos Giavridis, Jacky Wei En Kung, Daniel Hugenroth, and Alastair Beresford discovered that the OpenSSH ObscureKeystrokeTiming feature did not work as expected. A remote attacker could possibly use this issue to determine timing information about keystrokes.
- Record
USN-6887-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
opensshAzure Linux:3 |
before 9.8p1-1 | 9.8p1-1 |
opensshAlpaquita:stream |
9.5_p1-r0 up to 9.8_p1-r0 | 9.8_p1-r0 |
opensshBellSoft Hardened Containers:stream |
9.5_p1-r0 up to 9.8_p1-r0 | 9.8_p1-r0 |
opensshDebian:13 |
before 1:9.8p1-1 | 1:9.8p1-1 |
opensshDebian:14 |
before 1:9.8p1-1 | 1:9.8p1-1 |
opensshSUSE:Linux Enterprise Module for Basesystem 15 SP6 |
before 9.6p1-150600.6.6.1 | 9.6p1-150600.6.6.1 |
openssh-askpass-gnomeSUSE:Linux Enterprise Module for Desktop Applications 15 SP6 |
before 9.6p1-150600.6.6.1 | 9.6p1-150600.6.6.1 |
opensshopenSUSE:Leap 15.6 |
before 9.6p1-150600.6.6.1 | 9.6p1-150600.6.6.1 |
openssh-askpass-gnomeopenSUSE:Leap 15.6 |
before 9.6p1-150600.6.6.1 | 9.6p1-150600.6.6.1 |
opensshSUSE:Linux Micro 6.0 |
before 9.6p1-2.1 | 9.6p1-2.1 |
opensshUbuntu:24.04:LTS |
before 1:9.6p1-3ubuntu13.4, plus listed versions 1:9.3p1-1ubuntu31:9.4p1-1ubuntu11:9.6p1-3ubuntu11:9.6p1-3ubuntu21:9.6p1-3ubuntu111:9.6p1-3ubuntu121:9.6p1-3ubuntu131:9.6p1-3ubuntu13.3 |
1:9.6p1-3ubuntu13.4 |
opensshopenSUSE:Tumbleweed |
before 9.6p1-11.1 | 9.6p1-11.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2024-39894 is a high vulnerability (CVSS 7.5) in Openbsd Openssh, published July 2, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.63%, the 76th percentile. Fixed in openssh 9.8p1-1.
References
openssh.com/txt/release-9.8
lists.mindrot.org/pipermail/openssh-unix-announce/2024-July/000158.html
openwall.com/lists/oss-security/2024/07/02/1
openwall.com/lists/oss-security/2024/07/03/6
security.netapp.com/advisory/ntap-20240712-0004
openwall.com/lists/oss-security/2024/07/23/4
Show 26 moreShow less
openwall.com/lists/oss-security/2024/07/23/6
openwall.com/lists/oss-security/2024/07/28/3
crzphil.github.io/posts/ssh-obfuscation-bypass
news.ycombinator.com/item?id=41508530
freebsd.org/security/advisories/FreeBSD-SA-25:01.openssh.asc
seclists.org/fulldisclosure/2024/Sep/33
nvd.nist.gov/vuln/detail/CVE-2024-39894
github.com/advisories/GHSA-g5qj-pfmg-p3jp
docs.bell-sw.com/security/cves/CVE-2024-39894
security-tracker.debian.org/tracker/CVE-2024-39894
suse.com/support/update/announcement/2024/suse-su-20242393-1
bugzilla.suse.com/1218215
bugzilla.suse.com/1224392
bugzilla.suse.com/1225904
bugzilla.suse.com/1227318
bugzilla.suse.com/1227350
suse.com/security/cve/CVE-2023-51385
suse.com/security/cve/CVE-2024-39894
suse.com/support/update/announcement/2025/suse-su-202520009-1
bugzilla.suse.com/1217950
bugzilla.suse.com/1226642
suse.com/security/cve/CVE-2023-48795
suse.com/security/cve/CVE-2024-6387
ubuntu.com/security/CVE-2024-39894
cve.org/CVERecord?id=CVE-2024-39894
ubuntu.com/security/notices/USN-6887-1