Is CVE-2026-101049 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-101049 being exploited in the wild.

How severe is CVE-2026-101049?

Medium severity, with a CVSS score of 6.5, published 27 September 2026.

Is there a fix for CVE-2026-101049?

A patch was published on 2026-06-26. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-101049 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-101049?

Check whether you run Heymrun Heym 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.

CVE-2026-101049: Heym authentication bypass in Slack webhook verification

CVE-2026-101049 · Severity: medium · CVSS 6.5 · Published 2026-09-27

Heym is a workflow automation platform that integrates with services like Slack and Telegram. When Slack trigger nodes are configured without credential IDs or have empty signing secrets, the webhook endpoint skips signature verification entirely. An attacker with the public webhook URL can forge Slack events to trigger workflows with the owner's privileges, such as sending messages, modifying data, or executing connected actions.

Technologies: Heymrun Heym. Vendors: Heymrun.

Quick answers

Is CVE-2026-101049 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-101049 being exploited in the wild.
How severe is CVE-2026-101049?: Medium severity, with a CVSS score of 6.5, published 27 September 2026.
Which products and versions are affected?: Heymrun Heym before 0.0.53.
Is there a fix for CVE-2026-101049?: A patch was published on 2026-06-26. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-101049 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-101049?: Check whether you run Heymrun Heym 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.

Technical details

The Slack webhook endpoint in backend/app/api/slack.py fails to validate request signatures when the trigger node lacks a credentialId or the signing_secret is empty, allowing unauthenticated attackers to craft POST requests to known webhook URLs that bypass authentication. The vulnerability is reachable when workflow trigger nodes are misconfigured at creation time or remain in a degraded state. The patch (version 0.0.53) now rejects such requests with a 400 response and validates credential configuration before signature checking.

Affected products

heymrun Heym before 0.0.53

Timeline

2026-06-26: disclosed
2026-06-26: patched

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.