# GO-2026-5809 - Hysteria has an authenticated UDP ACL bypass that enables localhost and private-network UDP SSRF in…

Source: https://junglewise.ai/threats/go-2026-5809-hysteria-has-an-authenticated-udp-acl-bypass-that-enables-fc136b8e  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-07  
License: CC BY 4.0 with a link back

Severity: info · Published 2026-07-07

Hysteria has an authenticated UDP ACL bypass that enables localhost and private-network UDP SSRF in github.com/apernet/hysteria/core

Technologies: [github.com/apernet/hysteria/core/v2 (Go)](https://junglewise.ai/threats/technologies/github-com-apernet-hysteria-core-v2). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Informational severity, published 7 July 2026.

**Which products and versions are affected?** github.com/apernet/hysteria/core (Go) SEMVER:introduced=0; github.com/apernet/hysteria/core/v2 (Go) SEMVER:introduced=0,fixed=2.9.2.

**Is there a fix for This vulnerability?** Yes. github.com/apernet/hysteria/core/v2 (Go): upgrade to 2.9.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run github.com/apernet/hysteria/core (Go) or github.com/apernet/hysteria/core/v2 (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/apernet/hysteria/core/v2 (Go): upgrade to 2.9.2 or later

  ```sh
  go get github.com/apernet/hysteria/core/v2@v2.9.2
  ```


## Affected products

- github.com/apernet/hysteria/core (Go) SEMVER:introduced=0
- github.com/apernet/hysteria/core/v2 (Go) SEMVER:introduced=0,fixed=2.9.2

## Related threats

- [apernet Hysteria UDP ACL bypass and SSRF](https://junglewise.ai/threats/apernet-hysteria-udp-acl-bypass-and-ssrf-b247b4ec)
- [GO-2026-5288 - Hysteria: A specially constructed quic package can crash the server OOM when the sniff is enabled in…](https://junglewise.ai/threats/go-2026-5288-hysteria-a-specially-constructed-quic-package-can-crash-89d3770b)
- [Hysteria: A specially constructed quic package can crash the server OOM when the sniff is enabled](https://junglewise.ai/threats/hysteria-a-specially-constructed-quic-package-can-crash-the-server-oom-8b6b3a75)