CVE-2026-3731
MediumCVSS 5.3Summary
In libssh up to 0.11.3, the functions sftp_extensions_get_name and sftp_extensions_get_data in src/sftp.c (SFTP Extension Name Handler component) can cause an out-of-bounds read when the idx argument is manipulated. The attack may be performed remotely. Upgrading to version 0.11.4 or 0.12.0 resolves the issue (patch 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60).
Risk Assessment
A remote attacker can trigger an out-of-bounds memory read, potentially leading to information disclosure or application crash. This affects confidentiality and availability.
Recommendation
Upgrade libssh to version 0.11.4 or 0.12.0. Apply patch 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60.
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A flaw in libssh: a remote authenticated client can issue SFTP_READ requests with an arbitrarily large length, causing the SFTP server to allocate excessive memory and potentially exhaust it.
Original NVD description (English source)
A weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS