Sensitive Cookie with Improper SameSite Attribute Affecting async-http-client package, versions <2.12.3-1+deb12u1


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.33% (26th percentile)

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  • Snyk IDSNYK-ECHOLATEST-ASYNCHTTPCLIENT-18601857
  • published10 Aug 2026
  • disclosed1 Jul 2026

Introduced: 1 Jul 2026

CVE-2026-55688  (opens in a new tab)
CWE-1275  (opens in a new tab)

How to fix?

Upgrade Echo:latest async-http-client to version 2.12.3-1+deb12u1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream async-http-client package and not the async-http-client package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.