Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Remotely triggerable with no authentication; impact bounded to throttle bypass enabling faster brute-force (I:L) and minor resource exhaustion potential (A:L), with no confidentiality impact.
Primary rating from Vendor (mitre).
CVSS VectorVendor: mitre
Lifecycle Timeline
2DescriptionCVE.org
sshd in OpenSSH before 10.4 does not always honor the minimum authentication delay.
AnalysisAI
OpenSSH sshd before version 10.4 fails to consistently enforce its built-in minimum authentication delay, undermining the rate-limiting defense designed to slow credential-guessing attacks against SSH services. All OpenSSH releases prior to 10.4 are affected across all platforms, enabling unauthenticated remote attackers to submit authentication attempts at a rate higher than the daemon intends to permit. No public exploit code has been identified and the vulnerability is absent from CISA KEV; however, the trivial attack complexity combined with OpenSSH's near-universal deployment footprint makes prompt patching appropriate.
Technical ContextAI
OpenSSH's sshd daemon implements a minimum authentication delay as a defense-in-depth control: after each failed or pending authentication attempt, sshd imposes a configurable pause before processing the next attempt, rate-limiting brute-force and credential-stuffing attacks at the server level. CWE-770 (Allocation of Resources Without Limits or Throttling) captures the root cause - under certain conditions the daemon does not consistently enforce this delay, allowing the resource (authentication attempt slots) to be consumed without the intended throttle. The affected software is the OpenBSD OpenSSH server identified by CPE cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*, covering all releases before 10.4. The flaw is within sshd's own rate-control enforcement logic, not in the SSH protocol itself; downstream distributions shipping any OpenSSH version prior to 10.4 inherit the exposure until they backport or upgrade.
RemediationAI
Upgrade to OpenSSH 10.4p1 or later, the vendor-released patch confirmed by release notes at https://www.openssh.org/releasenotes.html#10.4p1. As a compensating control prior to upgrade, disable password-based and keyboard-interactive authentication in sshd_config by setting PasswordAuthentication no and KbdInteractiveAuthentication no, enforcing public-key-only login; this eliminates the practical value of bypassing the authentication delay since public-key negotiation is not brute-forceable in the same manner, though it will lock out users who have not configured SSH keys. Deploying external rate-limiting via firewall rules (e.g., iptables/nftables connection-rate limits on TCP/22) or intrusion-prevention tools such as fail2ban or sshguard provides an additional layer that compensates for the missing internal delay; note these tools may block legitimate users on shared egress IPs or NAT environments. Restricting SSH access to trusted source IP allowlists at the network perimeter is the most effective and lowest-overhead compensating control for environments with predictable access patterns.
GNU Bash through 4.3 processes trailing strings after function definitions in the values of environment variables, which
GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables, whi
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freeSSHd.exe in freeSSHd through 1.2.6 allows remote attackers to bypass authentication via a crafted session, as demons
GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables, whi
OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. Rated medium se
sshd in OpenSSH before 7.3, when SHA256 or SHA512 are used for user password hashing, uses BLOWFISH hashing on a static
The kbdint_next_device function in auth2-chall.c in sshd in OpenSSH through 6.9 does not properly restrict the processin
The auth_password function in auth-passwd.c in sshd in OpenSSH before 7.3 does not limit password lengths for password a
Remote code execution in OpenSSH's sshd server (regression of CVE-2006-5051) allows unauthenticated remote attackers to
The SSH USERAUTH CHANGE REQUEST feature in SSH Tectia Server 6.0.4 through 6.0.20, 6.1.0 through 6.1.12, 6.2.0 through 6
A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. Rated medium severity (CVSS 6.8), this
Same technique Denial Of Service
View allVendor StatusVendor
SUSE
Severity: Moderate| Product | Status |
|---|---|
| SLES15-SP5-CHOST-BYOS-SAP-CCloud | Affected |
| SLES15-SP6-CHOST-BYOS | Affected |
| SLES15-SP6-CHOST-BYOS-Aliyun | Affected |
| SLES15-SP6-CHOST-BYOS-Azure | Affected |
| SLES15-SP6-CHOST-BYOS-EC2 | Affected |
| SLES15-SP6-CHOST-BYOS-GCE | Affected |
| SLES15-SP6-CHOST-BYOS-GDC | Affected |
| SLES15-SP6-CHOST-BYOS-SAP-CCloud | Affected |
| SLES15-SP7-CHOST-BYOS-Aliyun | Affected |
| SLES15-SP7-CHOST-BYOS-Azure | Affected |
| SLES15-SP7-CHOST-BYOS-EC2 | Affected |
| SLES15-SP7-CHOST-BYOS-GCE | Affected |
| SLES15-SP7-CHOST-BYOS-GDC | Affected |
| SLES15-SP7-CHOST-BYOS-SAP-CCloud | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Micro 5.3 | Affected |
| SUSE Linux Enterprise Micro 5.4 | Affected |
| SUSE Linux Enterprise Micro 5.5 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Affected |
| SUSE Linux Micro 6.0 | Affected |
| SUSE Linux Micro 6.1 | Affected |
| SUSE Linux Micro 6.2 | Affected |
| openSUSE Leap 16.0 | Affected |
| SLES15-SP3-CHOST-BYOS-Aliyun | Affected |
| SLES15-SP3-CHOST-BYOS-Azure | Affected |
| SLES15-SP3-CHOST-BYOS-EC2 | Affected |
| SLES15-SP3-CHOST-BYOS-GCE | Affected |
| SLES15-SP3-CHOST-BYOS-SAP-CCloud | Affected |
| SLES15-SP4-CHOST-BYOS | Affected |
| SLES15-SP4-CHOST-BYOS-Aliyun | Affected |
| SLES15-SP4-CHOST-BYOS-Azure | Affected |
| SLES15-SP4-CHOST-BYOS-EC2 | Affected |
| SLES15-SP4-CHOST-BYOS-GCE | Affected |
| SLES15-SP4-CHOST-BYOS-SAP-CCloud | Affected |
| SLES15-SP5-CHOST-BYOS-Aliyun | Affected |
| SLES15-SP5-CHOST-BYOS-Azure | Affected |
| SLES15-SP5-CHOST-BYOS-EC2 | Affected |
| SLES15-SP5-CHOST-BYOS-GCE | Affected |
| SLES15-SP5-CHOST-BYOS-GDC | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | Affected |
| SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | Not-Affected |
| SUSE Linux Enterprise Server 12 SP5 | Not-Affected |
| SUSE Linux Enterprise Server 12 SP5 | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | Not-Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | Affected |
| SUSE Linux Enterprise Server 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5 | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Not-Affected |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE CaaS Platform 3.0 | Not-Affected |
| SUSE CaaS Platform 4.0 | Not-Affected |
| SUSE Enterprise Storage 6 | Not-Affected |
| SUSE Enterprise Storage 7 | Affected |
| SUSE Enterprise Storage 7.1 | Affected |
| SUSE Linux Enterprise Desktop 11 SP4 | Not-Affected |
| SUSE Linux Enterprise Desktop 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Desktop 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Desktop 12 SP4 | Not-Affected |
| SUSE Linux Enterprise Desktop 15 SP1 | Not-Affected |
| SUSE Linux Enterprise Desktop 15 SP2 | Affected |
| SUSE Linux Enterprise Desktop 15 SP3 | Affected |
| SUSE Linux Enterprise Desktop 15 SP4 | Affected |
| SUSE Linux Enterprise Desktop 15 SP5 | Affected |
| SUSE Linux Enterprise Desktop 15 SP6 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Not-Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Not-Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Not-Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Affected |
| SUSE Linux Enterprise Micro 5.0 | Affected |
| SUSE Linux Enterprise Micro 5.1 | Affected |
| SUSE Linux Enterprise Micro 5.2 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | Not-Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | Not-Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT | Not-Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | Affected |
| SUSE Linux Enterprise Server 11 SP4 | Not-Affected |
| SUSE Linux Enterprise Server 11 SP4-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2-BCL | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2-ESPOS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3-BCL | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3-ESPOS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP4 | Not-Affected |
| SUSE Linux Enterprise Server 15 SP1 | Not-Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | Not-Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 15 SP2 | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP3 | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise Server for Raspberry Pi 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Manager Proxy 4.0 | Not-Affected |
| SUSE Manager Proxy 4.1 | Affected |
| SUSE Manager Proxy 4.2 | Affected |
| SUSE Manager Retail Branch Server 4.0 | Not-Affected |
| SUSE Manager Retail Branch Server 4.1 | Affected |
| SUSE Manager Retail Branch Server 4.2 | Affected |
| SUSE Manager Server 4.0 | Not-Affected |
| SUSE Manager Server 4.1 | Affected |
| SUSE Manager Server 4.2 | Affected |
| SUSE OpenStack Cloud 7 | Not-Affected |
| SUSE OpenStack Cloud 8 | Not-Affected |
| SUSE OpenStack Cloud Crowbar 8 | Not-Affected |
| openSUSE Leap 15.3 | Affected |
| openSUSE Leap 15.4 | Affected |
| openSUSE Leap 15.5 | Affected |
| openSUSE Leap 15.6 | Affected |
| openSUSE Leap Micro 5.2 | Affected |
| openSUSE Leap Micro 5.3 | Affected |
| openSUSE Leap Micro 5.4 | Affected |
| openSUSE Leap Micro 5.5 | Affected |
| SLES-CHOST-BYOS-Aliyun | Affected |
| SLES-CHOST-BYOS-Azure | Affected |
| SLES-CHOST-BYOS-EC2 | Affected |
| SLES-CHOST-BYOS-GCE | Affected |
| SLES-CHOST-BYOS-GDC | Affected |
| SLES-CHOST-BYOS-SAP-CCloud | Affected |
| kiwi-templates-Minimal kiwi-templates-Minimal-Cloud-sap kiwi-templates-Minimal-MS-HyperV-sap kiwi-templates-Minimal-VMware-sap kiwi-templates-Minimal-kvm-and-xen-sap ses/7.1/cephcsi/cephcsi ses/7.1/rook/ceph ses/7/ceph/ceph ses/7/cephcsi/cephcsi ses/7/rook/ceph suse/hpc/warewulf4-x86_64/sle-hpc-node suse/manager/4.3/proxy-ssh suse/manager/5.0/x86_64/proxy-ssh suse/manager/5.0/x86_64/server suse/multi-linux-manager/5.1/x86_64/proxy-ssh suse/multi-linux-manager/5.1/x86_64/server suse/multi-linux-manager/5.2/x86_64/proxy-ssh suse/multi-linux-manager/5.2/x86_64/server suse/sle-micro-rancher/5.2 suse/sle-micro-rancher/5.3 suse/sle-micro-rancher/5.4 suse/sle-micro/5.5 trento/trento-runner | Affected |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-42145
GHSA-8pmr-cc7f-4v7w