CVE-2026-116844

Fclairamb ftpserverlib through 0.32.4 contains a cleartext transmission vulnerability because TransferOpen checks only the transferTLS flag set by PROT, not whether the prepared data connection uses TLS. When a client sends PROT P after PASV or PORT, file contents and directory listings cross the network unencrypted, even with mandatory encryption, letting on-path attackers read or modify them.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/fclairamb/ftpserverlib/blob/v0.32.4/client_handler.go#L720
https://github.com/fclairamb/ftpserverlib/blob/v0.32.4/handle_misc.go#L29-L31
https://github.com/fclairamb/ftpserverlib/pull/685
https://www.vulncheck.com/advisories/fclairamb-ftpserverlib-through-0.32.4-cleartext-ftpes-data-transfer-via-prot-p

Configurations

No configuration.

History

27 Oct 2026, 01:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-27 01:19

Updated : 2026-10-29 11:17

NVD link : CVE-2026-116844

Mitre link : CVE-2026-116844

CVE.ORG link : CVE-2026-116844

JSON object : View

Products Affected

No product.

CWE

CWE-319

Cleartext Transmission of Sensitive Information

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