CVE Catalog

CVE-2026-116844

MediumCVSS 4.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.09%

0th percentile - higher than 0% of all known CVEs

Summary

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.

Risk Assessment

An on-path attacker can read or modify transmitted data, compromising confidentiality and integrity.

Recommendation

Update ftpserverlib to a version later than 0.32.4 that properly verifies TLS usage for data connections.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS