VulnerabilityPublished 17 Sep 2026

CVE-2026-85719: AsyncHttpClient async-http-client · Cleartext Transmission

Affects AsyncHttpClient async-http-clientSource CVE Database V5

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Not known to be exploited · CVSS 7.5 High : upgrade to 3.0.12 or 2.16.1 soon.

Data as of 1 Nov 2026, 11:03 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 29% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 3.0.12, 2.16.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 1 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade async-http-client and org.asynchttpclient/async-http-client to 3.0.12 or 2.16.1.

Affected software

Product	Affected	Fixed in
AsyncHttpClientasync-http-client	Affected >=3.0.0 <3.0.12	Fixed in 3.0.12
AsyncHttpClientasync-http-client	Affected >=2.1.0 <2.16.1	Fixed in 2.16.1
Mavenorg.asynchttpclient/async-http-client`pkg:maven/org.asynchttpclient/async-http-client`Other threats	Affected >=2.1.0 <2.16.1 >=3.0.0 <3.0.12	Fixed in 2.16.1 3.0.12

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Upgrade AsyncHttpClient to version 2.16.1 or later, or 3.0.12 or later, where this vulnerability is fixed. No other mitigation is required as the fix is official and addresses the issue directly.

Description

AsyncHttpClient versions from 2.1.0 up to but not including 2.16.1 and from 3.0.0 up to but not including 3.0.12 allow proxy credentials to be exposed in cleartext. This occurs when using an authenticated SOCKS proxy, where the Proxy-Authorization header is attached to requests without verifying the proxy type, potentially exposing sensitive credentials to the origin server. The issue is fixed in versions 2.16.1 and 3.0.12.

Impact

Exploitation of this vulnerability can lead to the exposure of sensitive proxy authentication credentials to the origin server, including Basic (which is directly reversible), NTLM, Kerberos, and SPNEGO credentials. This compromises the confidentiality of proxy credentials but does not affect data integrity or availability. The CVSS score of 7.5 indicates a high severity impact with network attack vector, no privileges required, and no user interaction needed.

CWE-319Cleartext Transmission of Sensitive Information (opens in a new tab)
Base weaknessLikelihood of exploit: HighOWASP Top 10 A04:2025: Cryptographic Failures (opens in a new tab)
The product transmits sensitive or security-critical data in cleartext in a communication channel that can be sniffed by unauthorized actors.
Architecture and Design
Before transmitting, encrypt the data using reliable, confidentiality-protecting cryptographic protocols.
Implementation
When using web applications with SSL, use SSL for the entire session from login to logout, not just for the initial login page.
Implementation
When designing hardware platforms, ensure that approved encryption algorithms (such as those recommended by NIST) protect paths from security critical data to trusted user applications.
OWASP Cheat Sheets
Transport Layer Protection (opens in a new tab)
TLS Cipher String (opens in a new tab)
User Privacy Protection (opens in a new tab)
Password Storage (opens in a new tab)
Cryptographic Storage (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.1 (opens in a new tab)
V9.2.2 (opens in a new tab)
V1.9.1 (opens in a new tab)
Attack patterns
Session Sidejacking (opens in a new tab)
Harvesting Information via API Event Monitoring (opens in a new tab)
Signature Spoofing by Mixing Signed and Unsigned Content (opens in a new tab)
Sniff Application Code (opens in a new tab)
Interception (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-522Insufficiently Protected Credentials (opens in a new tab)
Class weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.
Architecture and Design
Use an appropriate security mechanism to protect the credentials.
Architecture and Design
Make appropriate use of cryptography to protect the credentials.
Implementation
Use industry standards to protect the credentials (e.g. LDAP, keystore, etc.).
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V2.10.3 (opens in a new tab)
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
Attack patterns
Session Sidejacking (opens in a new tab)
Signature Spoofing by Key Theft (opens in a new tab)
Password Recovery Exploitation (opens in a new tab)
Kerberoasting (opens in a new tab)
Modify Existing Service (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Sep 2026, 04:17 UTC

WeaknessesCWE-319, CWE-522

Technical details

References

Community reviews

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