SSH
CVE-2024-6409
HIGH
Vulnerability Assessment
| Weakness |
CWE
|
| Impact | CVSS score of 7.0 (HIGH). Attack characteristics: network attack vector, high complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAI
A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). Rated high severity (CVSS 7.0), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affected ProductsAI
See vendor advisory for affected versions.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified under CWE-364. A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server.
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Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
Primary rating from Vendor (redhat) · only source for this CVE.
CVSS VectorVendor: redhat
DescriptionCVE.org
A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
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
GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed function definitions in the values of
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
The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path, leading to remot
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
An issue was discovered in OpenSSH 7.9. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no
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