Who contributed to Vercel on June 12, 2026?

3 developers shipped this update, including gr2m, aayush-kapoor, and unstubbable.

What were the notable Vercel updates?

fix(provider-utils,ai): harden download SSRF guard against hostname and redirect bypasses (#15980), fix(provider-utils): cancel response body on download rejection to prevent socket leak, and fix(mcp): lock first sse endpoint received via event.

Jun 12, 2026

$ the-wire · showcase

VERCEL AI HARDENS AGAINST SSRF AND SOCKET LEAKS, NEXT.JS CACHE LAYER GETS DEV PERSISTENCE

By RepoJournal · Filed 06:00 UTC on June 12, 2026 · About Vercel · Composed from the cited sources · methodology

3 people shipped this

gr2m @gr2m 1 cited

aayush-kapoor @aayush-kapoor 1 cited

unstubbable @unstubbable 1 cited

Vercel AI shipped critical fixes to block three classes of SSRF bypasses in download validation, while Next.js dev server now persists private cache entries across reloads.

The AI SDK's `downloadBlob`, `download`, and MCP client functions had multiple security gaps in their URL validation and socket handling that have been patched [1][2]. The SSRF guard now blocks hostname tricks and redirect bypasses, and rejected downloads properly cancel their response bodies to prevent TCP socket leaks that could pile up under sustained load [2]. On the MCP side, once a client receives its first valid SSE endpoint, that URL stays locked in and later endpoint events are ignored, preventing a malicious event from hijacking subsequent tool calls [3]. Meanwhile, Next.js dev server improvements make cache behavior more realistic: private `'use cache'` entries now persist in a built-in in-memory handler so warm reloads stay fast [4], and stale cache entries serve until actual expiration rather than dropping at revalidate time [5]. The Vercel CLI got two wins for integration discovery: `vercel integration discover --category <slug>` filters the marketplace, and a new `vercel integration categories` subcommand lists valid slugs [7]. Node framework preset detection now works without package.json, defaulting to ESM format for a bare `server.ts` [6].

Action items

→ Update @vercel/ai to latest patch immediately if you use downloadBlob or MCP clients with untrusted URLs vercel/ai [immediate]
→ Review your next dev cache patterns; private cache now persists by default in development vercel/next.js [plan]
→ If you're using custom OpenAPI specs, upgrade to latest vercel CLI to use --spec-url flag vercel/vercel [monitor]
→ Monitor Workflow runs for duplicate hook_created events; idempotency fix now prevents spurious conflicts vercel/workflow [monitor]

References

[1] fix(provider-utils,ai): harden download SSRF guard against hostname and redirect bypasses (#15980) ↗ vercel/ai
[2] fix(provider-utils): cancel response body on download rejection to prevent socket leak ↗ vercel/ai
[3] fix(mcp): lock first sse endpoint received via event ↗ vercel/ai
[4] Persist `'use cache: private'` entries in dev (#94694) ↗ vercel/next.js
[5] Serve stale `'use cache'` entries in the dev server until they expire ↗ vercel/next.js
[6] Support Node framework preset without a package.json (#16614) ↗ vercel/vercel
[7] [cli] Add --category filter + integration categories subcommand (#16576) ↗ vercel/vercel