9router: Image prefetch DNS rebinding allows SSRF to internal services

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

9Router is an AI router & token saver. Prior to 0.5.2, 9router validates image URLs by resolving the host before fetching, but open-sse/translator/concerns/image.js performs the later server-side image fetch with a separate DNS resolution. An authenticated attacker with access to the LLM proxy can use a vision-capable model and an attacker-controlled DNS name that first resolves to a public IP and then rebinds to an internal address, allowing server-side requests to internal-only HTTP services. This issue is fixed in version 0.5.2.

[ Fixes ]Fixes and patches

• 9router 0.5.2Fixed version · GitHub Advisories · npm package 9router: upgrade to 0.5.2 or later (affected <= 0.4.80)

[ Packages ]Affected open-source packages

• 9router npmAffected <= 0.4.80 · fixed in 0.5.2 · GHSA-cmhj-wh2f-9cgx

[ References ]References

• github.com/decolua/9router/security/advisories/GHSA-cmhj-wh2f-9cgxx_refsource_CONFIRM
• github.com/decolua/9router/commit/c7d07448c58bec1200741de0b73305b860416b82x_refsource_MISC
• github.com/decolua/9router/releases/tag/v0.5.2x_refsource_MISC