CVE-2026-58051: high-severity vulnerability in libssh2
libssh2 - Free of Uninitialized Pointer in publickey List Cleanup
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
41Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 8.3epss 0.3%
libssh2 through 1.11.1 grows its publickey list with SSH2_REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2_publickey_list_free operating on an uninitialized entry. A malicious SSH server offering the publickey subsystem can use a malformed response to make cleanup free an uninitialized, attacker-influenceable attrs pointer in a connecting libssh2 client.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Affected products
libssh2 · libssh2public PoCs found — 1
cve_referencegithub.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-pocunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — libssh2
In the same product, most dangerous first.
CVE-2026-55200CRITICALlibssh2 - Out-of-Bounds Write via Unchecked packet_length in transport.cEPSS 3.9%CVE-2026-55199HIGHlibssh2 - Pre-Authentication DoS via SSH_MSG_EXT_INFO HandlerEPSS 0.9%CVE-2025-15661HIGHlibssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.cEPSS 0.6%CVE-2026-66033HIGHlibssh2 Integer Underflow DoS via AES-GCM Cipher NegotiationEPSS 0.6%CVE-2026-66035HIGHlibssh2 Heap Buffer Overflow via ETM Cipher NegotiationEPSS 0.5%CVE-2026-66032HIGHlibssh2 Double-Free Heap Corruption via sftp_open()EPSS 0.4%