Vulnerability · Published Sep 15, 2026 · Assigned by GitHub_M

CVE-2026-54637Dragonfly scheduler v1 gRPC unauthenticated SSRF via attacker-controlled PeerHost in DownloadTinyFile

Medium 5.5

In plain English

A medium-severity server-side request forgery in dragonfly from dragonflyoss. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 57% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)5.5Medium
Exploit odds (30 days)0.8%top 43.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Dragonfly is an open source P2P-based file distribution and image acceleration system. Prior to 2.4.4-rc.3, the scheduler's default unauthenticated v1 gRPC flow accepts attacker-controlled PeerHost.Ip and PeerHost.DownPort values through RegisterPeerTask and ReportPeerResult, storeHost copies those values into resource.Host, and handlePeerSuccess invokes Peer.DownloadTinyFile() for a TINY task. DownloadTinyFile() in scheduler/resource/standard/peer.go builds an HTTP GET request from the supplied address without destination validation, allowing a remote attacker to probe loopback, link-local, and private services and place up to TinyFileSize, 128 bytes, of a response in Task.DirectPiece for later retrieval. PeerHost.DownPort is restricted to ports 1024 through 65534, and the issue provides read SSRF rather than remote code execution. The remediation blocks loopback and link-local targets, while RFC1918 destinations remain reachable because IsGlobalUnicast accepts private ranges. This issue is fixed in 2.4.4-rc.3.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
God7y.io/dragonfly/v22.4.4-rc.3GHSA-chwm-m7g7-685g
God7y.io/dragonfly/v22.4.4-rc.3GO-2026-5910

Affected products (as reported)

VendorProductVersions
dragonflyoss dragonfly < 2.4.4-rc.3

Weakness: CWE-918 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

References