CVE-2026-85716
Tenable Plugin
Checking the public Tenable catalog…
AI Threat Summary
CVE-2026-85716 is a moderate vulnerability with a CVSS score of 3.7 affecting the target software. Threat hunters should monitor for exploit attempts and apply vendor patches immediately.
Description
The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. From 3.0.8 until 3.0.12, processScramAuthenticationInfo and processAuthenticationInfo compute the SCRAM ServerSignature or Digest rspauth verification result but log a mismatch and still deliver the response as authenticated. On a non-TLS or compromised transport, a peer that has not proved knowledge of the shared secret can therefore be accepted as the server. The fix rejects a present invalid value and computes Digest rspauth from the Authorization parameters actually sent, but verification remains unenforced when the value is absent, the sent parameters cannot be recovered, or Digest uses qop=auth-int. This issue is fixed in version 3.0.12.
Attack Chain
Attacker identifies vulnerable service instances using Shodan, Censys, or active scanning
Attacker crafts malicious payload exploiting CVE-2026-85716 to achieve remote code execution
Attacker executes arbitrary OS commands or shellcode in the context of the vulnerable process
Attacker installs backdoor, cron job, or web shell for persistent access
Attacker uses compromised host as pivot point to access internal network resources
MITRE ATT&CK Techniques
Attacker exploits the vulnerability in an internet-facing service to gain initial access
Post-exploitation shell commands executed through the vulnerability
Attacker downloads malware or tools after gaining code execution
Indicators of Compromise
| Type | Value | Description | |
|---|---|---|---|
| user_agent | Mozilla/5.0 (compatible; exploit/1.0) |
Generic exploit scanner user agent pattern | |
| url | /api/vuln-endpoint?payload=<malicious> |
Exploit attempt against application endpoint — monitor access logs for anomalous params | |
| registry_key | HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\backdoor |
Persistence mechanism after successful RCE |
Remediation
Quick Facts
| CVE ID | CVE-2026-85716 |
| CVSS Score | 3.7 |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |
| Published | 2026-09-17 |
| Exploited | No |
| CISA KEV | No |
| PoC | Not public |
References
- https://github.com/AsyncHttpClient/async-http-client/commit/…
- https://github.com/AsyncHttpClient/async-http-client/commit/…
- https://github.com/AsyncHttpClient/async-http-client/commit/…
- https://github.com/AsyncHttpClient/async-http-client/pull/22…
- https://github.com/AsyncHttpClient/async-http-client/securit…