CVE-2026-52856: Pterodactyl Wings denial of service in SFTP handshake

CVE-2026-52856 · Severity: high · CVSS 7.5 · Published 2026-07-31

Pterodactyl Wings, the software responsible for managing and controlling game servers, is vulnerable to a denial-of-service attack. An attacker can send a specially crafted network packet during the file transfer (SFTP) login process to crash the service. This would result in the management panel becoming unavailable and potentially interrupting game server operations until the service is manually restarted.

Technologies: github.com/pterodactyl/wings (Go), Pterodactyl Wings. Vendors: Go, Pterodactyl.

Quick answers

Is CVE-2026-52856 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-52856 being exploited in the wild.
How severe is CVE-2026-52856?
High severity, with a CVSS score of 7.5, published 31 July 2026.
Which products and versions are affected?
github.com/pterodactyl/wings (Go) < 1.13.0, SEMVER:introduced=0,fixed=1.13.0; Pterodactyl Wings < 1.13.0.
Is there a fix for CVE-2026-52856?
Yes. github.com/pterodactyl/wings (Go): upgrade to 1.13.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-52856 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-52856?
Check whether you run github.com/pterodactyl/wings (Go) or Pterodactyl Wings at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/pterodactyl/wings (Go): upgrade to 1.13.0 or later
    go get github.com/pterodactyl/wings@v1.13.0

Technical details

A vulnerability in the SFTP server component of Pterodactyl Wings (prior to version 1.13.0) allows for a remote denial-of-service. The flaw exists in the 'AcceptInbound' function within 'sftp/server.go', where the code attempts to slice the 'req.Payload' array without first verifying that the payload contains at least 4 bytes. An attacker sending a malformed packet with a payload smaller than 4 bytes triggers an out-of-bounds array index access, resulting in a Go runtime panic and service crash. This can be executed by an unauthenticated attacker over the network. The issue is resolved in version 1.13.0 by adding a length check before the slicing operation.

Affected products

  • Pterodactyl Wings < 1.13.0

Identifiers

  • CVE-2026-52856
  • GHSA-ghrq-5wpp-hxx5
  • GO-2026-6156

Timeline

  • 2026-06-15: advisory: GitHub Security Advisory published
  • 2026-06-15: patched: Version 1.13.0 released
  • 2026-07-31: disclosed: NVD publication date

References

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