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CVE-2026-59842

Status: AnalyzedMedium (5.3)—

A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (11)

Libssh — LibsshRedhat — Enterprise LinuxRedhat — Enterprise Linux FOR ELSRedhat — Enterprise Linux FOR EUSRedhat — Enterprise Linux FOR IBM Z SystemsRedhat — Enterprise Linux FOR IBM Z Systems ELSRedhat — Enterprise Linux FOR IBM Z Systems EUSRedhat — Enterprise Linux FOR Power Little EndianRedhat — Enterprise Linux FOR Power Little Endian ELSRedhat — Enterprise Linux FOR Power Little Endian EUSRedhat — Hardened Images

CWEs

References

Raw JSON (NVD)

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