How severe is CVE-2026-107285?

CVE-2026-107285 has a CVSS score of 5.9/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-107285?

CVE-2026-107285 affects the following packages: org.asynchttpclient:async-http-client (Maven), org.asynchttpclient:async-http-client (Maven). Ecosystems affected: Maven.

How do I fix CVE-2026-107285?

Update org.asynchttpclient:async-http-client to 3.0.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-107285 is resolved across your whole dependency graph.

How do I detect CVE-2026-107285 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.asynchttpclient:async-http-client, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-107285 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2026-107285 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-107285 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-107285?

CVE-2026-107285 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 10th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-107285?

CVE-2026-107285 is classified as CWE-319 (CWE-319), CWE-522 (CWE-522). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-107285 published, and has it been updated?

CVE-2026-107285 was published on October 7, 2026 and was last updated on October 21, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

MEDIUM severity

CVE-2026-107285 — async-http-client

MEDIUMFix: AsyncHttpClient/async-http-client@6e9cb75

CVE-2026-107285 is a medium-severity (CVSS 5.9) CWE-319 vulnerability in org.asynchttpclient:async-http-client. A fix is available for org.asynchttpclient:async-http-client — see the affected versions and patch details below.

AsyncHttpClient: WebSocket proxy credentials sent to the origin server over a CONNECT tunnel

Also known asGHSA-3wp9-xfwm-rjjf

Published

Oct 7, 2026

Updated

Oct 21, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-107285.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs10th percentile — riskier than 10% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2026-107285 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

☕org.asynchttpclient:async-http-client☕org.asynchttpclient:async-http-client

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Impact

When a ws:// request is routed through an HTTP proxy with proxy authentication configured, the client tunnels the connection with an HTTP CONNECT, the same as it does for https://. Once the tunnel is open, the WebSocket upgrade request that follows is sent through the tunnel directly to the origin server, not to the proxy. The proxy-auth gate and the companion request-target selection keyed only on whether the URI was secured, which is false for ws://, so the tunnelled upgrade request incorrectly carried the proxy's Proxy-Authorization header and an absolute-form request target meant for the proxy. Any origin server reached over a proxied ws:// connection, or anyone positioned on the origin side of the wire, could recover the proxy credentials: directly for Basic, or as a replayable and offline-crackable response for Digest.

Affected versions

3.x: up to and including 3.0.11
2.x: up to and including 2.16.0

Patches

Fixed in 3.0.12 on the 3.x line and in 2.16.1 on the 2.x line. The preemptive Proxy-Authorization header and the absolute-form request target are no longer attached to a tunnelled ws:// upgrade; a ws:// request is now treated like wss://.

Workarounds

Do not use proxy authentication together with ws:// requests through an HTTP proxy, or use wss:// instead.

Details

The proxy-auth gate in NettyRequestFactory#newNettyRequest and the sibling branch in requestUri() did not exclude WebSocket URIs, even though the CONNECT-tunnelling check in NettyRequestSender already tunnels ws:// through CONNECT exactly like https://.

Note that 3.0.12 is itself affected by a separate issue, GHSA-rqf5-2wxv-rjf4, where a Digest challenge the client cannot read downgrades to Basic and sends the password in cleartext. Upgrade to 3.0.13 to pick up both fixes.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.asynchttpclient:async-http-client`	≥ 3.0.0&&< 3.0.12	3.0.12`org.asynchttpclient:async-http-client:3.0.12`
☕Maven	`org.asynchttpclient:async-http-client`	≥ 2.0.0&&< 2.16.1	2.16.1`org.asynchttpclient:async-http-client:2.16.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.asynchttpclient:async-http-client, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.asynchttpclient:async-http-client to 3.0.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-107285 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

### Impact When a ws:// request is routed through an HTTP proxy with proxy authentication configured, the client tunnels the connection with an HTTP CONNECT, the same as it does for https://. Once the tunnel is open, the WebSocket upgrade request that follows is sent through the tunnel directly to the origin server, not to the proxy. The proxy-auth gate and the companion request-target selection keyed only on whether the URI was secured, which is false for ws://, so the tunnelled upgrade request incorrectly carried the proxy's Proxy-Authorization header and an absolute-form request target mean