CVE-2026-54637

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

MEDIUM
5.5
CVSS Score
Published: September 15, 2026 at 02:04 PM UTC
Updated: September 30, 2026 at 05:51 PM UTC
1 product affected across 1 vendorDragonfly

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Severity
MEDIUM5.5
Exploit prediction
EPSS 0.8%
SSVC
PoC

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.4.4-rc.3
Affected range stops below 2.4.4-rc.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.5MEDIUMGitHub_M
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-918

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