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pin Bun 1.4.4, which fixes the Brotli decoder's out-of-bounds write (CVE-2026-111497) - #144
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Why
Bun before 1.4.4 has CVE-2026-111497 ("Node2Shell"), an out-of-bounds write in its Brotli decoder. Bun's
fetchdecompresses aContent-Encoding: branswer by itself, so any server the api fetches from can send a crafted one. For a custom MCP connection, that server is whatever URL the person typed in: discovery (mcp-discovery.ts) and every tool call (custom-mcp.ts) fetch it. So anyone who signs up could reach the decoder with input they choose, in the process that holdsENCRYPTION_KEYandDATABASE_URL. A public proof of concept came out on October 22. No attacks have been reported yet.Bun 1.4.4 came out on October 22, and
oven/bun:1-slimpoints to it now. The images were built from that floating tag, though, so a build that reuses a cached base layer can still ship 1.4.3.What
Dockerfile: both stages areFROM oven/bun:1.4.4-slim, with a comment saying why it's pinned.render.yaml: the docs' and website'sBUN_VERSIONgoes from 1.4.2 to 1.4.4, the version the image is built with, as its comment says. They are build-only static sites, so they were never exposed.Express 4 / body-parser 1.x doesn't decompress Brotli request bodies, so inbound requests were never a way in.
Testing
/healthand the web app answer 200, andbun --versionin the container is1.4.4.bun run teston Bun 1.4.4: all packages pass (api 828, web 182, integrations 50, utils 46, db 14, map 2, ui 1).Rollout
Merging deploys the pinned image. Until then, prod may be running ≤ 1.4.3: it depends on whether today's deploys pulled the new base image, which we can't see from outside.