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CVE-2026-55200

Status: AnalyzedCritical (9.2)—

libssh2 through 1.11.1, fixed in commit 7acf3df contains an out-of-bounds write vulnerability in ssh2_transport_read() that fails to enforce upper bounds on packet_length field. Remote attackers can send crafted SSH packets with excessively large packet_length values to corrupt heap memory and achieve remote code execution.

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).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vector CVSS:4.0 con AV:N (red, sin privilegios) y ausencia de UI:R indican explotación remota sin interacción (T1190). El desbordamiento de buffer en ssh2_transport_read() permite corrupción de memoria heap y RCE, confirmado por CWE-680.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account ManagementVulnerability ScanningRestrict Web-Based ContentNetwork SegmentationLimit Software InstallationLimit Access to Resource Over Network

Affected technologies (1)

Libssh2 — Libssh2

CWEs

References

Raw JSON (NVD)

Show
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    }
  ],
  "lastModified": "2026-09-17T17:04:42.983",
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