SSRF in Hatchet-Dev Hatchet

CVE-2026-61681

Hatchet is a platform for orchestrating background tasks, AI agents, and durable workflows at scale. Prior to 0.91.1, the SNS UnsubscribeConfirmation handler in internal/integrations/ingestors/sns/sns.go calls http.Get() on payload.UnsubscribeURL after VerifyPayload() even though BuildSignature() excludes UnsubscribeURL, allowing an authenticated Hatchet tenant to replace that field in an otherwise valid AWS-signed message with an internal URL. The server-side request can reach EC2 Instance Metadata Service, internal services, and internal HTTP APIs, potentially exposing IAM credentials or network-accessible data and functionality. This issue is fixed in version 0.91.1.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-61681: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-61681?
CVE-2026-61681 is a medium-severity vulnerability in Hatchet-Dev Hatchet, classified under Server-Side Request Forgery (SSRF). CVSS score: 4.1/10. Published 2026-09-21.
How severe is CVE-2026-61681?
Medium severity. CVSS v3 base score is 4.1 out of 10.