CVE-2026-116844: fclairamb ftpserverlib · Cleartext Transmission
Affects fclairamb ftpserverlibSource CVE Database V5
Not known to be exploited · CVSS 6.3 Medium.
Data as of 27 Oct 2026, 01:27 UTC
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 27 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| fclairambftpserverlib | Affected
| Fixed in– |
Goftpserverlibpkg:golang/ftpserverlibOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, users should consider alternative secure FTP implementations or additional network-layer encryption to protect data confidentiality.
Description
fclairamb ftpserverlib versions up to 0.32.4 have a vulnerability where sensitive information such as file contents and directory listings can be transmitted in cleartext. This occurs because the software only checks a transferTLS flag set by the PROT command, not whether the actual data connection uses TLS. As a result, even with mandatory encryption configured, data can be sent unencrypted if the client sends PROT P after PASV or PORT commands, exposing data to on-path attackers.
References
- github.com/fclairamb/ftpserverlib/pull/685 (opens in a new tab)
- github.com/fclairamb/ftpserverlib/blob/v0.32.4/handle_misc.go (opens in a new tab)
- github.com/fclairamb/ftpserverlib/blob/v0.32.4/client_handler.go (opens in a new tab)
- vulncheck.com/advisories/fclairamb-ftpserverlib-through-0.32.4-cleartext-ftpes-data-transfer-via-prot-p (opens in a new tab)