CVE-2026-55200

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 v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/libssh2/libssh2/commit/97acf3dfda80c91c3a8c9f2372546301d4a1a7a8
https://github.com/libssh2/libssh2/pull/2052
https://www.vulncheck.com/advisories/libssh2-out-of-bounds-write-via-unchecked-packet-length-in-transport-c

Configurations

No configuration.

History

18 Jun 2026, 04:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 20:17

Updated : 2026-06-22 18:43

NVD link : CVE-2026-55200

Mitre link : CVE-2026-55200

CVE.ORG link : CVE-2026-55200

JSON object : View

Products Affected

No product.

CWE

CWE-680

Integer Overflow to Buffer Overflow

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