CVE-2026-107231 AsyncHttpClient: Digest challenge without a usable nonce downgrades to Basic and sends the password in cleartext
A malicious server or proxy can force the AsyncHttpClient library to downgrade Digest authentication to Basic, exposing user credentials in cleartext.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-107231?
CVE-2026-107231 is a high-severity vulnerability in AsyncHttpClient async-http-client, published on 7 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. Prior to 3.0.13 and 2.16.1, Realm.Builder treats a Digest challenge that yields no usable nonce as a Basic challenge. A malicious origin or proxy can label a challenge Digest while omitting or emptying the nonce, causing the client to resend the username and password using reversible Basic authentication. Both origin and proxy challenge parsers are affected. This issue is fixed in versions 3.0.13 and 2.16.1.
Which versions are affected by CVE-2026-107231?
4 open source packages ship an affected version, including org.asynchttpclient:async-http-client.
| Package | Affected | Fixed in |
|---|---|---|
org.asynchttpclient:async-http-client Maven | From 2.0.0 | 2.16.1 |
org.asynchttpclient:async-http-client Maven | From 2.0.0 | 2.16.1 |
org.asynchttpclient:async-http-client Maven | From 3.0.0.Beta1 | 3.0.13 |
org.asynchttpclient:async-http-client Maven | From 3.0.0.Beta1 | 3.0.13 |
How do I fix CVE-2026-107231?
Upgrade org.asynchttpclient:async-http-client to a fixed version for your release line: 2.16.1 or 3.0.13.
Is CVE-2026-107231 being exploited?
There is no known exploitation of CVE-2026-107231 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-107231, ECHO-32cd-c594-6bfe, GHSA-rqf5-2wxv-rjf4, MINI-cmq8-5hpf-jc57, MINI-mcwr-r6q6-7hcq, MINI-qrr3-j75j-6g4f and 3 more.