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CriticalVulnerabilityCVE-2026-119568updated 30 Oct 2026, 16:09 UTC

vsftpd FTPS data connections can be hijacked by unauthenticated attackers

Someone on the same network address as a user of this FTP server could potentially take over that user's file transfers, stealing downloaded files or injecting data into uploads. No password is needed for the attacker.

Official, 2 sources
SeverityCriticalCVSS 9.1 of 10
Being exploited?UnclearNo reports either way yet
Fix available?UnclearNo fixed version published in the sources yet
How sure is this?Official, 2 sourcesBacked by an official source

How the attack works simplified

  1. 1Attacker on same IPShares the victim's source address
  2. 2Obtains TLS ticketVia AUTH TLS, no login needed
  3. 3Connects to PASV portTargets the victim's data connection
  4. 4Steals or injects dataDownloads read, uploads altered
  5. ResultVictim's file transfers are hijacked

What happened

vsftpd through 3.0.5 has an authentication bypass in ssl_data_accept(): an unauthenticated client can resume its own TLS session ticket to hijack FTPS data connections to the PASV port of a victim sharing the same source IP.

Why it is dangerous: Attackers can steal files being downloaded or inject malicious data into uploads, compromising confidentiality and integrity of file transfers. Anyone running vsftpd with FTPS enabled and shared source IPs, such as users behind NAT, is at risk.

Are you affected?

You are affected if you run vsftpd 3.0.5 or earlier with FTPS (TLS) enabled for data connections.

vsftpd through 3.0.5

What to do

  1. Check whether your vsftpd version is 3.0.5 or earlier and whether FTPS is enabled
  2. Disable FTPS or restrict FTP access to trusted networks until a fixed version is available
  3. Watch the vsftpd project and the GitHub advisory for a patched release and update as soon as one is published

Timeline

  1. 30 Oct 2026, 12:16 UTC
    Publicly disclosed
  2. 30 Oct 2026, 12:16 UTC
    Reported by NVD · NVD
  3. 30 Oct 2026, 12:21 UTC
    Picked up by Zero Radar
  4. 30 Oct 2026, 16:09 UTC
    GitHub Advisory reported on it · GitHub Advisory

Sources 2 reports, oldest first

Official vendor, government CERT or advisory database

Technical details

ID
CVE-2026-119568 · GHSA-93qj-4wg6-29x9
CVSS
9.1 / 10
EPSS
0.4% chance of exploitation within 30 days
Disclosed
30 Oct 2026, 12:16 UTC
On Zero Radar
30 Oct 2026, 12:21 UTC (5 min after disclosure)
Last change
30 Oct 2026, 16:09 UTC

The plain-language parts and the attack diagram were written by an AI model (anthropic/claude-haiku-5.5) from the sources above. Facts like versions, exploitation and dates come from the sources themselves. How Zero Radar works

vsftpd FTPS data connections can be hijacked by unauthenticated attackers · Zero Radar