AsyncHttpClient: Cookie stored for an unrelated domain (cookie tossing) via ThreadSafeCookieStore
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Partial Red Hat: 1 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. In versions from 2.0.0 prior to 2.16.0 and from 3.0.0.Beta1 prior to 3.0.11, ThreadSafeCookieStore stored a cookie under the value of its Domain attribute without verifying that the responding host is allowed to set a cookie for that domain, leading to a cookie tossing / cookie injection issue. A host the client connects to can therefore plant a cookie scoped to an unrelated domain, and the client will then send that cookie on later requests to that domain. Applications that use a single AsyncHttpClient instance - and thus the default, shared CookieStore - to reach both an attacker-influenced host and a trusted host are impacted. This issue has been fixed in versions 2.16.0 and 3.0.11.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| AsyncHttpClient | async-http-client | 2.0.0 to before 2.16.0; 3.0.0.Beta1 to before 3.0.11 | 2.16.0, 3.0.11 | Patch available | CNA |
| — | org.asynchttpclient:async-http-client (Maven) | 3.0.0.Beta1 to before 3.0.11 | 3.0.11 | Patch available | GHSA-m452-q8c9-rg2f |
| — | org.asynchttpclient:async-http-client (Maven) | 2.0.0 to before 2.16.0 | 2.16.0 | Patch available | GHSA-m452-q8c9-rg2f |
- async-http-client VendorAsyncHttpClient Affected 2.0.0 to before 2.16.0; 3.0.0.Beta1 to before 3.0.11 Fixed in 2.16.0, 3.0.11 Patch available CNA
- org.asynchttpclient:async-http-client (Maven) Vendor— Affected 3.0.0.Beta1 to before 3.0.11 Fixed in 3.0.11 Patch available GHSA-m452-q8c9-rg2f
- org.asynchttpclient:async-http-client (Maven) Vendor— Affected 2.0.0 to before 2.16.0 Fixed in 2.16.0 Patch available GHSA-m452-q8c9-rg2f
Remediation
- Fix · CNA async-http-client (AsyncHttpClient) Fixed in 2.16.0, 3.0.11
- Fix · GHSA-m452-q8c9-rg2f org.asynchttpclient:async-http-client (Maven) Fixed in 3.0.11 Advisory →
- Fix · GHSA-m452-q8c9-rg2f org.asynchttpclient:async-http-client (Maven) Fixed in 2.16.0 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat JBoss Enterprise Application Platform Expansion Pack | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-55688
- 2026-10-03 Alias added: GHSA-m452-q8c9-rg2f
References
Other 9
- https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-m452-q8c9-rg2f
- https://github.com/AsyncHttpClient/async-http-client/pull/2196
- https://github.com/AsyncHttpClient/async-http-client/pull/2199
- https://github.com/AsyncHttpClient/async-http-client/commit/8e4069cf3c92abe099db5fb13378ac2fe9e1fd3b
- https://github.com/AsyncHttpClient/async-http-client/commit/e6955c1e3951cf80e286981d064f6c926ce33f47
- https://github.com/AsyncHttpClient/async-http-client
- https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-2.16.0
- https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-3.0.11
- https://lists.debian.org/debian-lts-announce/2026/08/msg00011.html
More AsyncHttpClient vulnerabilities
- TI-2024-36149 AsyncHttpClient (AHC) library's `CookieStore` replaces explicitly defined `Cookie`s CVSS 4.0CRITICAL 9.2
- TI-2026-69321 Cross-host replay in AsyncHttpClient leaks credentials to new host CVSS 4.0CRITICAL 9.4
- TI-2026-69315 AsyncHttpClient sends passwords in cleartext after Digest downgrade CVSS 4.0HIGH 8.7
- TI-2026-58825 AsyncHttpClient: Unbounded HTTP/1.1 response decompression enables a decompression-bomb denial of service CVSS 3.1HIGH 7.5
- TI-2026-69311 Unbounded WebSocket decompression in AsyncHttpClient enables DoS CVSS 3.1HIGH 7.5
- TI-2026-58823 AsyncHttpClient: SOCKS proxy credentials sent to the origin server over plaintext HTTP CVSS 3.1HIGH 7.5
Sources
- CVE-2026-55688 · CVE Program
- CVE-2026-55688 · NVD
- FIRST EPSS
- GHSA-m452-q8c9-rg2f · GitHub Advisory Database · CC BY 4.0
- CVE-2026-55688 · Red Hat security data · CC BY 4.0
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