Libssh
CVE-2023-2283
MEDIUM
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Lifecycle Timeline
1DescriptionNVD
A vulnerability was found in libssh, where the authentication check of the connecting client can be bypassed in thepki_verify_data_signature function in memory allocation problems. This issue may happen if there is insufficient memory or the memory usage is limited. The problem is caused by the return value rc, which is initialized to SSH_ERROR and later rewritten to save the return value of the function call pki_key_check_hash_compatible. The value of the variable is not changed between this point and the cryptographic verification. Therefore any error between them calls goto error returning SSH_OK.
AnalysisAI
A vulnerability was found in libssh, where the authentication check of the connecting client can be bypassed in thepki_verify_data_signature function in memory allocation problems. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Improper Authentication (CWE-287), which allows attackers to bypass authentication mechanisms to gain unauthorized access. A vulnerability was found in libssh, where the authentication check of the connecting client can be bypassed in thepki_verify_data_signature function in memory allocation problems. This issue may happen if there is insufficient memory or the memory usage is limited. The problem is caused by the return value rc, which is initialized to SSH_ERROR and later rewritten to save the return value of the function call pki_key_check_hash_compatible. The value of the variable is not changed between this point and the cryptographic verification. Therefore any error between them calls goto error returning SSH_OK. Affected products include: Libssh, Fedoraproject Fedora, Redhat Enterprise Linux.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement multi-factor authentication, enforce strong password policies, use proven authentication frameworks.
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Same weakness CWE-287 – Improper Authentication
View allSame technique Authentication Bypass
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External POC / Exploit Code
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