CVE-2026-54637CWE-918ssrf

CVE-2026-54637

published September 15, 2026

CVSS
5.5
EPSS
1%
Percentile
56.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS
5.5 · NONE
CVSS v4.0
5.5 · 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
EPSS
0.00800 · 56.1th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-09-15T19:17Z
References (4)
EPSS history
Timeline
  • 17 SEP 03:31Z
    EPSS moved — → 0%
    epss
  • 15 SEP 14:04Z
    Dragonfly scheduler v1 gRPC unauthenticated SSRF via attacker-controlled PeerHost in DownloadTinyFile
    cvelistv5