CVE-2025-15661

libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/libssh2/libssh2/commit/2dae3024897e1898d389835151f4e9606227721d
https://github.com/libssh2/libssh2/pull/1705
https://github.com/libssh2/libssh2/pull/1717
https://www.vulncheck.com/advisories/libssh2-heap-buffer-over-read-via-sftp-symlink-in-sftp-c

Configurations

No configuration.

History

18 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-18 21:16

Updated : 2026-06-18 21:16

NVD link : CVE-2025-15661

Mitre link : CVE-2025-15661

CVE.ORG link : CVE-2025-15661

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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