# CVE-2026-61681: Hatchet SSRF in SNS UnsubscribeConfirmation handler

Source: https://junglewise.ai/threats/cve-2026-61681-hatchet-ssrf-in-sns-unsubscribeconfirmation-handler  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-21. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-61681 · Severity: medium · CVSS 4.1 · Published 2026-09-21

Hatchet is a workflow orchestration platform that integrates with AWS SNS for event processing. An attacker with valid Hatchet and AWS credentials can inject a malicious URL into SNS unsubscribe messages, causing the Hatchet server to make unauthorized HTTP requests to internal services—including cloud metadata endpoints that expose IAM credentials, internal APIs, and other non-public infrastructure.

Technologies: [github.com/hatchet-dev/hatchet (Go)](https://junglewise.ai/threats/technologies/github-com-hatchet-dev-hatchet), [Hatchet](https://junglewise.ai/threats/technologies/hatchet). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Hatchet](https://junglewise.ai/threats/vendors/hatchet).

## Quick answers

**Is CVE-2026-61681 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-61681 being exploited in the wild.

**How severe is CVE-2026-61681?** Medium severity, with a CVSS score of 4.1, published 21 September 2026.

**Which products and versions are affected?** github.com/hatchet-dev/hatchet (Go) SEMVER:introduced=0; hatchet-dev/hatchet (Go) < 0.91.1, SEMVER:introduced=0,fixed=0.91.1; Hatchet < 0.91.1.

**Is there a fix for CVE-2026-61681?** Yes. hatchet-dev/hatchet (Go): upgrade to 0.91.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-61681 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-61681?** Check whether you run github.com/hatchet-dev/hatchet (Go), hatchet-dev/hatchet (Go) or Hatchet 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

- hatchet-dev/hatchet (Go): upgrade to 0.91.1 or later

  ```sh
  go get hatchet-dev/hatchet@v0.91.1
  ```


## Technical details

The SNS UnsubscribeConfirmation handler in internal/integrations/ingestors/sns/sns.go performs an unvalidated HTTP GET request to payload.UnsubscribeURL without any URL filtering. The UnsubscribeURL field is intentionally excluded from the AWS signature validation (BuildSignature() function), allowing an attacker to replace it with an arbitrary URL while the rest of the message remains cryptographically signed and valid. An authenticated attacker with an AWS account can craft a malicious SNS message and trigger SSRF, enabling access to EC2 Instance Metadata Service (IMDS) at 169.254.169.254, internal Kubernetes APIs, dashboards, and internal HTTP services. The vulnerability requires an attacker to have a valid Hatchet account and AWS Free Tier account. A fix was released in version 0.91.1.

## Affected products

- Hatchet Hatchet < 0.91.1

## Identifiers

- CVE-2026-61681
- GHSA-fjwv-jf2v-j499
- GO-2026-6565

## Timeline

- 2026-06-30: disclosed: Published to GitHub Advisory Database
- 2026-06-30: patched: Fix released in version 0.91.1
- 2026-09-21: advisory: Published by National Vulnerability Database
- 2026-09-22: other: GitHub Advisory reviewed and updated

## References

- [https://api.github.com/users/aslein1413-sys](https://api.github.com/users/aslein1413-sys)

## Related threats

- [Hatchet resource exhaustion via SNS ingestion endpoint](https://junglewise.ai/threats/cve-2026-108755-hatchet-through-0-110-5-contains-an-allocation-of-resources)
- [Hatchet DurableTask WorkerStatus gRPC authorization bypass via unfiltered tenant_id](https://junglewise.ai/threats/cve-2026-88978-hatchet-durabletask-workerstatus-grpc-authorization-bypass-via)
- [Hatchet cross-tenant durable callback payload disclosure](https://junglewise.ai/threats/cve-2026-84298-hatchet-cross-tenant-durable-callback-payload-disclosure)
- [Hatchet authorization bypass in durable task event log endpoint](https://junglewise.ai/threats/cve-2026-63342-hatchet-authorization-bypass-in-durable-task-event-log-endpoint)
- [Hatchet OAuth state CSRF via empty-state collision](https://junglewise.ai/threats/cve-2026-61687-hatchet-oauth-state-csrf-via-empty-state-collision)